BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Hot isostatic pressing of ion exchange materials\, from the Fukush ima and Sellafield sites\, to produce ceramic wasteforms. DTSTART:20171031T213000Z DTEND:20171031T220000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1111@events.synchrotron.org.au DESCRIPTION:Speakers: Paul Heath (The University of Sheffield\, now at Geo roc Ltd.)\, Claire Corkhill (The University of Sheffield)\, Martin Stennet t (The University of Sheffield)\, Stephanie Thornber (The University of Sh effield)\, Laura Gardner (The University of Sheffield)\, Neil Hyatt (Unive rsity of Sheffield)\n\nDecommissioning and clean up of nuclear facilities requires the development of new technologies to condition radioactive wast es\, producing passively safe waste packages of minimal volume\, to reduce storage and disposal costs. We have applied hot isostatic pressing to de monstrate conceptual wasteforms for ion exchange materials and sludges pre sent on the Sellafield site\, UK\, and Fukushima site\, Japan. These radi oactive wastes pose several challenges which demand early conditioning to produce a passively safe wasteform\, including: i) the materials are of a wet and granular nature\, and hence dispersible as a result of loss of con tainment\; ii) the materials are characterised by very high dose rates as a result of their selectivity for short lived radionuclides (e.g. Sr-90\, Cs-137\, Co-60)\; iii) the materials exhibit radiogenic self heating\, as a result of the concentration of such lived radio nuclides\; iv) the mater ials exhibit hydrogen production as a result of radiolysis of entrained wa ter.\nIn this presentation we demonstrate the conversion of several commer cial and natural inorganic ion exchange materials into multiphase ceramic wasteforms\, achieving a waste loading of 100 wt% and density in excess of 97% theoretical. High resolution thermogravimetric analysis coupled with mass spectroscopy was utilised to characterise the evolution of water and volatiles during the in-can bake out step\, prior to the HIP cycle. This allowed optimisation of the bake out parameters (temperature\, time and v acuum) to enable complete removal of water and volatiles\, affording ceram ic bodies with minimal residual porosity by hot isostatic pressing at 1250 oC for 4h in stainless steel cans. Characterisation of the ceramic wastefo rms by SEM /EDX and X-ray diffraction revealed the nuclides of concern to be incorporated within well known natural mineral and synthetic phases\, w ith Sr partitioning into the SrTiO3 pervoskite phase and Co\, Fe\, Mn and Cr partitioning into a spinel phase. Dynamic alteration experiments revea led matrix dissolution rates of less than 10-4 g m-2 d-1 under forward rat e conditions at 90 oC.\nOverall\, hot isostatic pressing of inorganic ion exchange materials yields durable glass\, glass-ceramic\, and ceramic wast eforms\, with minimal voidage and porosity\, in which the radionuclide par titioning between glass and ceramic phases can be controlled by wasteform composition and processing parameters. The resulting ceramic wasteforms a re considered to meet the disposability requirements of a UK Geological Di sposal Facility for radioactive wastes.\n\nhttps://events.synchrotron.org. au/event/51/contributions/1111/ URL:https://events.synchrotron.org.au/event/51/contributions/1111/ END:VEVENT BEGIN:VEVENT SUMMARY:Towards understanding the dissolution of vitrified nuclear waste i n a cementitious geological disposal facility DTSTART:20171031T000000Z DTEND:20171031T003000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1112@events.synchrotron.org.au DESCRIPTION:Speakers: Neil Hyatt (NucleUS Immobilisation Science Laborator y\, University of Sheffield)\, Russell Hand (NucleUS Immobilisation Scienc e Laboratory\, University of Sheffield)\, Adam Fisher (NucleUS Immobilisat ion Science Laboratory\, University of Sheffield)\, Daniel Backhouse (Nucl eUS Immobilisation Science Laboratory\, University of Sheffield)\, Colleen Mann (NucleUS Immobilisation Science Laboratory\, University of Sheffield )\, Claire Corkhill (NucleUS Immobilisation Science Laboratory\, Universit y of Sheffield\,)\n\nUnder the generic scenario envisaged for the geologic al disposal of vitrified UK high- and intermediate-level waste glass (HLW and ILW\, respectively)\, high pH environments\, formed through degradatio n of the cementitious engineered barrier\, are expected to dominate the gr ound water chemistry thousands of years into the future. We highlight the main findings of a number of recent and ongoing studies that aim to evalua te and understand how cementitious groundwater compositions influence the dissolution rate of vitrified wasteforms\, including: simulant UK HLW\; th e International Simple Glass\; natural basaltic glass and glasses designed for ILW. Briefly\, we discuss results detailing the mechanisms of alterat ion layer formation in Ca-rich systems\; we describe the influence of idea lised cement leachate solutions on ion-exchange processes during the initi al stages of dissolution\; and we review the application of single-pass fl ow-through methods to derive the fundamental parameters necessary to model the dissolution kinetics of vitrified waste.\n\nhttps://events.synchrotro n.org.au/event/51/contributions/1112/ URL:https://events.synchrotron.org.au/event/51/contributions/1112/ END:VEVENT BEGIN:VEVENT SUMMARY:The Corrosion of Copper Nuclear Waste Containers under Deep Geolog ic Disposal ConditionsF DTSTART:20171030T060000Z DTEND:20171030T061500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1113@events.synchrotron.org.au DESCRIPTION:Speakers: Sridhar Ramamurthy (Western University)\, Dmitrij Za gidulin (Western University)\, James Noel (Western University)\, David Sho esmith (Western University)\n\nThe corrosion of high level copper nuclear waste containers under permanent disposal conditions can occur via a numbe r of processes which change in importance as the environment within a deep geologic repository evolves from warm and oxic to cool and anoxic. Under warm and oxic conditions the container could be exposed to gamma irradiate d conditions which evolve from aerated vapour to fully saturated aqueous c onditions. During this period the possibility of localized corrosion (e.g. \, pitting) must be considered. Over extended exposure periods when anoxic conditions prevail corrosion will be sustained by reaction with sulphide produced either by remote microbial activity or the dissolution of sulphid es present in the clays compacted around the container. Studies to underst and and quantify both these corrosion processes are underway. In this pres entation these studies will be discussed and their use in the development of corrosion models described.\n\nhttps://events.synchrotron.org.au/event/ 51/contributions/1113/ URL:https://events.synchrotron.org.au/event/51/contributions/1113/ END:VEVENT BEGIN:VEVENT SUMMARY:Radiation stability study of melt processed and hot isostatically pressed multi-phase ceramic waste forms DTSTART:20171031T050000Z DTEND:20171031T051500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1116@events.synchrotron.org.au DESCRIPTION:Speakers: Jake W. Amoroso (Savannah River National Laboratory) \, Eric R. Vance (Australian Nuclear Science and Technology Organisation)\ , Ming Tang (Los Alamos National Laboratory)\n\nMulti-phase ceramic waste forms were fabricated by melt-processing and hot isostatic pressing (HIP) to immobilize alkaline/alkaline earth (Cs/Sr-CS) + lanthanide (LN) + trans ition metal (TM) fission product waste streams from nuclear fuel reprocess ing. Al2O3 and TiO2 were combined with these waste components to produce multi-phase crystalline ceramics containing hollandite-type phases\, perov skites\, zirconolite/pyrochlores and other minor phases. In this study\, i on irradiations are performed to test and compare radiation tolerance of m ulti-phase ceramics produced via melting processing and HIP techniques. \ nFor the radiation stability test\, selected crystalline ceramic samples a re exposed to charge particles generated by an ion accelerator\, which is used to simulate self-radiation in a waste form. Ion irradiation-induced microstructural modifications\, volume swelling and microcracking are exam ined using X-ray diffraction\, transmission electron microscopy\, scanning electron microscopy and other characterization methods. Our preliminary results reveal similar radiation tolerance in these multi-phase ceramics w ith different fabrication techniques.\n\nhttps://events.synchrotron.org.au /event/51/contributions/1116/ URL:https://events.synchrotron.org.au/event/51/contributions/1116/ END:VEVENT BEGIN:VEVENT SUMMARY:Nuclear Waste Management update in Australia DTSTART:20171029T231500Z DTEND:20171029T234500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1117@events.synchrotron.org.au DESCRIPTION:Speakers: Hefin Griffiths (ANSTO)\n\nAustralia is currently in the process of establishing a National Radioactive Waste Management Facil ity and seeking to identify a site to host the facility. \nThe lecture wil l focus on the history of waste production in Australia\, the current mana gement of the diverse waste arisings\, particularly focussed on operationa l and legacy wastes held at the Australian Nuclear Science and Technology Organisation and the strategy applied to the management of those wastes.\n The process adopted to establish the facility will be discussed as well as potential future options for the disposal of Intermediate Level Wastes. A ustralia’s focus on investing in optimum wasteforms\, such as the vitrif ied residues from reprocessing spent fuel elements from current and previo us research reactors and the synroc waste form for treating Intermediate L evel Liquid Wastes\, will be discussed as case studies.\n\nhttps://events. synchrotron.org.au/event/51/contributions/1117/ URL:https://events.synchrotron.org.au/event/51/contributions/1117/ END:VEVENT BEGIN:VEVENT SUMMARY:Interaction of nuclear safeguards and safety requirements when pla nning for waste disposal DTSTART:20171030T213000Z DTEND:20171030T220000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1118@events.synchrotron.org.au DESCRIPTION:Speakers: Rebecca Stohr (Australian Safeguards and Non-Prolife ration Office)\n\nWaste conditioning is an important step in minimising an d controlling the migration of radionuclides from disposed wastes into the environment. However\, when nuclear materials are present\, consideration of nuclear safeguards is also needed. Safeguards is the set of tools and techniques used to ensure nuclear materials are only used for peaceful pur poses. As part of a safeguards system\, nuclear materials need to be avail able for verification or rendered inaccessible in accordance with Internat ional Atomic Energy Agency requirements. Inaccessibility requirements are not driven by environmental degradation factors\, but on preventing recove ry by motivated state actors. This presentation looks at the overlap betwe en safety and safeguards requirements in Australia as well as safeguards-s pecific requirements when conditioning or disposing of nuclear materials.\ n\nhttps://events.synchrotron.org.au/event/51/contributions/1118/ URL:https://events.synchrotron.org.au/event/51/contributions/1118/ END:VEVENT BEGIN:VEVENT SUMMARY:The development of zirconolite glass-ceramics for the immobilisati on of Pu-residues in the UK. DTSTART:20171101T030000Z DTEND:20171101T031500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1120@events.synchrotron.org.au DESCRIPTION:Speakers: Martin Stennett (University of Sheffield)\, Neil Hya tt (The University of Sheffield)\, Stephanie Thornber (University of Sheff ield)\n\nThe UK has over 100 tonnes of separated PuO2 stored at the Sellaf ield site. The UK policy for managing this plutonium stockpile is to reuse this material as MOx fuel. However\, not all of the material is suitable for reuse and a proportion has been classified as higher activity waste. These plutonium wastes\, and any material which is not ultimately reused\, will require immobilization\, in a passively safe wasteform\, for long-te rm storage and eventual geological disposal. One proposed treatment plan i s hot isostatic pressing of the plutonium waste / stockpile material\, wit h suitable precursors\, to form a glass-ceramic or full ceramic wasteform\ , inside stainless steel canisters. Glass-ceramic materials are proposed f or the low purity and highly variable wastes\, in which the glass phase pr ovides wasteform flexibility to accommodate impurities and variations in t he waste feed composition. The plutonium partitions into the more durable ceramic phase\, zirconolite (CaZrTi2O7). Zirconolite has excellent wastefo rm properties including durability and radiation tolerance\, and readily a ccepts actinides and rare earths into its crystal structure.\n\nIn this wo rk\, the formation of zirconolite is shown to depend sensitively on glass fraction and composition\, such that an Al rich glass promotes a higher yi eld of zirconolite. The thermodynamic activity of Si in the system drives the crystalline phase assemblage\, by determining whether it is consumed i n the amorphous glass phase or undesired accessory crystalline phases\, su ch as sphene (CaTiSiO5) and zircon (ZrSiO4). The design of an optimized g lass-ceramic formulation is demonstrated\, to maximize the yield of zircon olite and minimise the yield of accessory phases. The partitioning of CeO 2\, within the glass-ceramic wasteform\, as a PuO2 surrogate\, was studied using various charge compensation mechanisms\, under an imposed Fe/FeO an d Ni/NiO buffer. Analysis by SEM/EDX\, XRD\, and Ce L3 edge XANES\, demon strated reduction of Ce(IV) to Ce(III) to favour incorporation of Ce withi n a perovskite accessory phase and the glass matrix. Ce partitioning in t he zirconolite phase was maximized when retained as Ce(IV). These results demonstrate a feasible wasteform formulation for disposition of UK pluton ium wastes and stockpile material.\n\nhttps://events.synchrotron.org.au/ev ent/51/contributions/1120/ URL:https://events.synchrotron.org.au/event/51/contributions/1120/ END:VEVENT BEGIN:VEVENT SUMMARY:Invited Lecture: Plutonium Waste Management in the UK DTSTART:20171029T234500Z DTEND:20171030T001500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1121@events.synchrotron.org.au DESCRIPTION:Speakers: Michael Slater (Invited Lecturer)\n\nPlutonium has a risen from large scale reprocessing over many decades. When the programmes ends around 2020 there will be approx. 140te of separated plutonium in UK . Current policy is safe and secure long term storage in modern purpose bu ilt stores. This requires ongoing active management and institutional cont rols including significant security costs and is not a lifecycle solution. Disposition options are being considered in order to put the material “ beyond reach”:\n• Reuse as LWR MOX\n• Reuse in Candu EC6 React ors (CANMOX)\n• Reuse in GEH Prism Fast Reactor\n• Immobilisatio n – Hot Isostatic Pressing (HIP) along with other technologies including low spec MOX and downblending.\nThe current status of these options will be outlined along with work planned over the next few years further develo p them in support of future UK Government policy decisions.\n\nhttps://eve nts.synchrotron.org.au/event/51/contributions/1121/ URL:https://events.synchrotron.org.au/event/51/contributions/1121/ END:VEVENT BEGIN:VEVENT SUMMARY:Efficient remediation of radiodine with silver-functionalized sili ca aerogel DTSTART:20171101T041500Z DTEND:20171101T044500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1122@events.synchrotron.org.au DESCRIPTION:Speakers: Josef Matyas (Pacific Northwest National Laboratory) \n\nVarious volatile radionuclides are being released into gas streams and aqueous solutions during reprocessing of used nuclear fuel and vitrificat ion of radioactive waste. Radioactive iodine-129 is of a particular conce rn because of its long half-life of 15.7 million years and the potential f or biological processes to concentrate iodine. A number of materials are being developed worldwide to capture and immobilize iodine in a waste form of a high chemical durability\; however\, none of them can be used as bot h a sorbent and a viable waste form. They can either encapsulate iodine-l oaded sorbent or sequester iodine that was removed from it. In the U.S.\, the current benchmark for radioiodine capture is reduced silver mordenite (AgZ) and that for the waste form is AgZ immobilized in a low-temperature glass composite material. However\, the primary alternative option is a silver-functionalized silica aerogel (Ag-aerogel). Ag-aerogel exhibits hi gh capture efficiency (~ 500 mg/g) and selectivity for iodine (DF> 10000)\ , and good resistance against aging in nuclear fuel reprocessing off-gas s treams. Its sorption performance is retained in deionized water and in a dilute salt solution with neutral pH containing iodide or iodate. A key a dvantage of an Ag-aerogel is that\, after loading with iodine\, it can be consolidated into a dense and high-iodine-loaded silica-based waste form b y simultaneous application of the heat and pressure. Presentation will di scuss the sorption performance of Ag-aerogel in different environments and provide an overview on the development of waste form.\n\nhttps://events.s ynchrotron.org.au/event/51/contributions/1122/ URL:https://events.synchrotron.org.au/event/51/contributions/1122/ END:VEVENT BEGIN:VEVENT SUMMARY:Digital autoradiography on C-14 labelled PMMA impregnated rock sam ples using the Beaver$^{TM}$ DTSTART:20171102T004500Z DTEND:20171102T010000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1123@events.synchrotron.org.au DESCRIPTION:Speakers: Marja Siitari-Kauppi (Department of Chemistry\, Univ ersity of Helsinki\, Finland)\, Samuel Duval (AI4R SAS\, Nantes\, France)\ , Jérôme Donnard (AI4R SAS\, Nantes\, France)\, Juuso Sammaljärvi (Depa rtment of Chemsistry\, University of Helsinki\, Finland)\, Mikko Voutilain en (Department of Chemistry\, University of Helsinki\, Finland)\n\nIn Finl and and Sweden KBS-3 concept has been chosen for disposal of spent nuclear fuel in crystalline rock. Recent transport experiments have shown that he terogeneity of rock may play a major role in transport of radionuclides. A utoradiographic methods has been proven to be able to assist the character ization of heterogeneous structures. In this study we tested a novel digit al autoradiographic device called Beaver$^{TM}$ which applies a Micro Patt erned Gaseous Detector in order to quantitatively map beta emissions by C- 14 atoms. The studied samples were impregnated with C-14 labelled MMA (Met hyl MethAcrylate) and polymerized to PMMA using heat. The Beaver$^{TM}$ wa s then used to determine concentration of C-14 atoms which can then be con verted to porosity based on the amount of C-14 intruded into the rock samp le. The resulting images show a heterogeneous distribution of porosity whi ch arises from the different porosities of minerals. The samples were chos en from three sites that has been used recently in *in situ* diffusion exp eriments: Olkiluoto (Finland)\, Äspö (Sweden) and Grimsel (Switzerland). \n\nhttps://events.synchrotron.org.au/event/51/contributions/1123/ URL:https://events.synchrotron.org.au/event/51/contributions/1123/ END:VEVENT BEGIN:VEVENT SUMMARY:Synthesis and characterisation of rare Ce3NbO7 compounds for use a s nuclear space batteries by neutron powder diffraction and X-ray absorpti on spectroscopy DTSTART:20171031T223000Z DTEND:20171031T224500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1125@events.synchrotron.org.au DESCRIPTION:Speakers: Shi-Kuan Sun (University of Sheffield)\, Emma McCabe (University of Kent)\, Martin Stennett (University of Sheffield)\, Neil H yatt (The University of Sheffield)\, Sean Barlow (University of Sheffield) \n\nCe3NbO7 weberite-type materials\, an inactive analogue for Am3NbO7\, h ave potential use in americium radioisotope thermoelectric generators to b e developed by the European Space Agency for scientific missions beyond th e orbit of Jupiter. Ceramics with greater than 97% purity were synthesised by thermal solid-state reaction and analytically characterised by X-ray d iffraction\, neutron diffraction\, helium pycnometry\, Raman spectroscopy and X-ray absorption spectroscopy. The Magnetochemistry of the system was calculated with the Weiss temperature and magnetic moment per unit volume derived\, in good agreement against the theoretical values. Reitveld refin ement of neutron data was employed to identify the crystal structure of th e novel cerium niobate and determine the correct orthorhombic space groupi ng from either Cmcm (No.63) or Pnma (No.62) space groups. Ce3NbO7 refined well under both systems indicating possible pseudosymmetry. Cerium in the +III oxidation state was observed by X-ray absorption spectroscopy confirm ing the chemical speciation within the structure.\n\nhttps://events.synchr otron.org.au/event/51/contributions/1125/ URL:https://events.synchrotron.org.au/event/51/contributions/1125/ END:VEVENT BEGIN:VEVENT SUMMARY:Comparison of calculated and measured radionuclide inventory of a Zircaloy-4 cladding tube plenum section DTSTART:20171030T063000Z DTEND:20171030T064500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1126@events.synchrotron.org.au DESCRIPTION:Speakers: Ernesto González-Robles (Karlsruhe Institute of Tec hnology)\, Volker Metz (Karlsruhe Institute of Technology)\, Ron Dagan (Ka rlsruhe Institute of Technology)\, Dieter Schild (Karlsruhe Institute of T echnology)\, Jörg Rothe (Karlsruhe Institute of Technology)\, Kathy Darde nne (Karlsruhe Institute of Technology)\, Nikolaus Müller (Karlsruhe Inst itute of Technology)\, Michel Herm (Karlsruhe Institute of Technology)\n\n Cladding tubes of water-cooled nuclear reactors are usually made of Zircal oy and are an important retaining element for radionuclides present in the fuel. However\, cladding integrity is affected by various processes durin g reactor operation and beyond\, e.g. oxidation\, hydrogen uptake\, PCI\, fission product precipitation\, alpha-decay\, and radiation damage. Using experimental and modelling methods\, the radionuclide inventory of an irra diated Zircaloy-4 plenum section is analyzed.\nQuantities of U-235/238\, N p-237\, Pu-238/239/240/241/242\, Am-241/243\, Cm-243/244 besides C-14\, Fe -55\, Sb-125\, Cs-134/137 were (radio-)chemically determined in digested Z ircaloy-4 subsamples. Measured inventories of activation products in the Z r-alloy are in good agreement with calculated values. However\, amounts of actinides and fission products exceed the calculated inventory by factor ~50 (Pu isotopes) and ~120 (Cs-137). Excess Pu and part of excess Cs inven tory originate from fuel residues on the inner cladding surface\, whereas vast amount of cesium is volatilized from subjacent fuel pellets and trans ported to the plenum.\n\nhttps://events.synchrotron.org.au/event/51/contri butions/1126/ URL:https://events.synchrotron.org.au/event/51/contributions/1126/ END:VEVENT BEGIN:VEVENT SUMMARY:Microparticle Production as Reference Materials for Particle Analy sis Methods in Safeguards DTSTART:20171030T231500Z DTEND:20171030T233000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1127@events.synchrotron.org.au DESCRIPTION:Speakers: Dirk Bosbach (Forschungszentrum Jülich GmbH\, Insti tute of Energy and Climate Research – Nuclear Waste Management and React or Safety (IEK-6)\, 52428 Jülich\, Germany)\, Irmgard Niemeyer (Forschung szentrum Jülich GmbH\, Institute of Energy and Climate Research – Nucle ar Waste Management and Reactor Safety (IEK-6)\, 52428 Jülich\, Germany)\ , Daniel Grolimund (Paul Scherrer Institute\, 5232 Villigen\, Switzerland) \, Valerie-Ann Samson (Paul Scherrer Institute\, 5232 Villigen\, Switzerla nd)\, Dario Ferreira Sanchez (Paul Scherrer Institute\, 5232 Villigen\, Sw itzerland)\, Fabien Pointurier (CEA\, DAM\, DIF\, F-91297 Arpajon\, France )\, Martina Klinkenberg (Forschungszentrum Jülich GmbH\, Institute of Ene rgy and Climate Research – Nuclear Waste Management and Reactor Safety ( IEK-6)\, 52428 Jülich\, Germany)\, Alexander Knott (European Commission\, Joint Research Centre Karlsruhe (JRC)\, 76344 Karlsruhe\, Germany)\, Rona ld Middendorp (Forschungszentrum Jülich GmbH\, Institute of Energy and Cl imate Research – Nuclear Waste Management and Reactor Safety (IEK-6)\, 5 2428 Jülich\, Germany)\, Stefan Neumeier (Forschungszentrum Jülich GmbH) \n\nThe application of safeguards measures by the International Atomic Ene rgy Agency (IAEA) involves analytical measurements of samples taken during inspections and requires the development and advancement of analytical te chniques. For quality control purposes\, the IAEA has expressed the need t o acquire reference materials for particle analysis methods applied in saf eguards.\n\nTo this purpose\, a particle production facility was implement ed at Forschungszentrum Jülich\, which is capable of producing microparti cles intended as source material for certified reference materials for par ticle analysis methods applied in safeguards. A monodisperse particle size distribution as well as the single phase triuranium octoxide structure wa s confirmed using SEM and µ-XRD/XANES\, respectively. Analysis performed on single uranium microparticles confirmed consistency of the uranium isot opic ratios in comparison to the initial precursor solutions. To improve t he homogeneity and particle handling\, the particles are transferred into suspensions\, for which the stability was investigated with respect to dis solution and isotopic exchange.\n\nhttps://events.synchrotron.org.au/event /51/contributions/1127/ URL:https://events.synchrotron.org.au/event/51/contributions/1127/ END:VEVENT BEGIN:VEVENT SUMMARY:Identification of chemical form of stable carbon released from typ e 304 and 316 stainless-steel powders in alkaline solution and in acidic s olution under low-oxygen condition DTSTART:20171102T043000Z DTEND:20171102T044500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1128@events.synchrotron.org.au DESCRIPTION:Speakers: Tomonari FUJITA (Central Research Institute of Elect ric Power Industry)\, Ryo Nakabayashi (Central Research Institute of Elect ric Power Industry)\n\nThe chemical form of carbon-14 released from irradi ated stainless steel is a key parameter in the safety assessment of the su b-surface disposal system in Japan. In this study\, unirradiated 304 and 3 16 stainless-steel powders were immersed in HCl solution and in NaOH solut ion under a low-oxygen condition to identify the chemical form of the rele ased carbon. The main chemical forms of the carbon were formic and acetic acids in the HCl solution and colloidal carbon in the NaOH solution. Point analysis of the colloidal particles by transmission electron microscopy e quipped with energy dispersive spectroscopy showed that C was accompanied with Fe and Cr. Fe and Cr tended to precipitate thermodynamically as hydro xides in an alkaline environment\, suggesting that carbon sorbed onto the hydroxide. Meanwhile\, in the HCl solution\, the hydroxides did not precip itate thermodynamically\, so carbon appeared to be released as an ionic fo rm without the formation of metallic hydroxides.\n\nhttps://events.synchro tron.org.au/event/51/contributions/1128/ URL:https://events.synchrotron.org.au/event/51/contributions/1128/ END:VEVENT BEGIN:VEVENT SUMMARY:Ion irradiation used as surrogate for neutron irradiation to under stand nuclear graphite evolution during reactor operation: consequences fo r the long lived radionuclide’s behavior DTSTART:20171031T054500Z DTEND:20171031T060000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1129@events.synchrotron.org.au DESCRIPTION:Speakers: Philippe Sainsot (Université de Lyon/INSA)\, Damien Deldicque (CNRS/ENS Paris)\, Patrick Simon (CNRS/CEMHTI)\, Mohamed Ramzi Ammar (CNRS/CEMHTI)\, Yves Pipon (Université de Lyon\, IUT Lyon 1)\, Nath alie Moncoffre (CNRS/IN2P3/IPNL)\, Nicolas Galy (CNRS/IN2P3/IPNL)\, Nelly TOULHOAT (CNRS/IN2P3/IPNL)\, Nicolas Bérerd (Université de Lyon\, IUT Ly on 1)\n\nGraphite has been widely used in different types of reactors such as gas or water cooled reactors. Disposal of the irradiated graphite wast e is a current management strategy for the resulting graphite waste for wh ich two main radionuclides\, 14C and 36Cl\, might be dose determining at t he outlet. In order to simulate both ballistic and electronic effects indu ced by irradiation\, model and nuclear graphite samples implanted with 37C l or 14C (to simulate the radionuclides) have been irradiated using ions b y varying the Sn(nuclear)/Se(electronic) stopping power ratio. Extrapolati ng to reactor irradiation\, we show that depending on the initial graphite ordering level and texture (binder/grain) and according to the subsequent neutron flux and temperature\, graphite irradiation results into a struct ural “zoning” impacting the radionuclide behavior: except when located close to open pores\, 14C is stabilized into graphite whereas 36Cl’s re lease is strongly correlated to the counteracting effects of irradiation a nd temperature.\n\nhttps://events.synchrotron.org.au/event/51/contribution s/1129/ URL:https://events.synchrotron.org.au/event/51/contributions/1129/ END:VEVENT BEGIN:VEVENT SUMMARY:Solubility of the rhabdophane\, LnPO4.0.667 H2O (Ln = La to Dy): i mplications for the long-term stability of monazite matrices. DTSTART:20171031T234500Z DTEND:20171101T001500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1130@events.synchrotron.org.au DESCRIPTION:Speakers: Stefan NEUMEIER (IEK-6 FZ Jülich)\, Nicolas Dacheux (ICSM)\, Nicolas Clavier (ICSM)\, adel mesbah (ICSM Marcoule\, France)\, Clémence Gausse (ICSM)\, Stéphanie Szenknect (ICSM)\n\nMinerals belongin g to the monazite family\, REEPO4 (REE: Y\, Sc\, La to Dy) could incorpora te in their structure substantial amounts of Th and U [1]. Moreover\, mona zites maintain their crystallinity even after geological times of exposure to self-irradiation. Therefore\, this phase appears as a promising candid ate for the specific conditioning of transuranic elements (AnIV\,AnIII). A lready\, many thermodynamic properties of monazite are reported in the lit terature [2]. However\, its hydrated form namely\, rhabdophane\, REEPO4.0. 667 H2O could be stabilized at low temperatures\, and thus control the con centrations of actinides in solution after the leaching of the monazite ma trices [3\, 4]. \n\nFor the first time\, a systematic study of the solubil ity of the rhabdophane\, LnPO4.0.667 H2O (Ln = La to Dy) was performed usi ng over-saturated and under-saturated experiments at different temperature s (298 to 363 K) to demonstrate the reversibility of the solubility equili brium [5]. The structure of the neoformed phases was carefully controlled in the entire range of temperatures in order to attribute unambiguously th e solubility products and the derived thermodynamic data associated to the rhabdophane phases. The obtained results indicate that the stability doma in of the rhabdophane phase is limited in temperature and depends on the i onic radius of the lanthanide. The values of the solubility constant depen d also slightly on the lanthanide with log KS\,0° (298 K) ranging from -2 5.6 ± 0.8 (Pr) to -24.9 ± 1.7 (Eu) with minimum values for Pr to Sm. The values of the standard free enery of formation at 298 K varied between -1 984 ± 2 and -2004 ± 2 kJ.mol-1 whatever the lanthanide element considere d\, except for Eu-rhabdophane that presented the highest value for the Gib bs energy of formation (-1896 ± 2 kJ.mol-1).\nFrom the solubility data ob tained at various temperatures\, the values of enthalpy of formation of th e rhabdophanes were found between -2151 ± 13 and -2130 ± 12 kJ. mol-1 ex cepted for Eu for which it reached -2057 ± 9 kJ.mol-1. It is worth noting that the data reported by Ushakov et al. [6] for monazites LnPO4 (Ln = La to Gd) determined by oxide melt calorimetry and recalculated by taking in to account the contribution of the water molecules are in very good agreem ent with the data obtained for rhabdophane in this work. This result indic ates that the enthalpy of formation of the rhabdophane can be simply deduc ed from the enthalpy of formation of the monazite by adding the contributi on of 0.667 molecule of structural water.\n\nThese results could be used t o estimate the thermodynamic properties of AnIIIPO4 .0.667 H2O (with AnIII =Am\, Pu or Cm) by analogy with the lanthanides of close ionic radii. The rhabdophane structure can also incorporate AnIV by coupled substitution o f LnIII by MII and AnIV. In this field\, Nd0.8Ca0.1Th0.1PO4 .n H2O were p repared by wet chemistry route and preliminary solubility data were determ ined\, which showed that this phase is metastable in solution at 298 K\, T h and Nd being released leading to the formation of Th2(PO4)2(HPO4). H2O ( TPHPH) [7] and NdPO4.0.667 H2O\, respectively.\n\nReferences:\n[1] N. Clav ier\, R. Podor\, N. Dacheux\, (2011). Journal of the European Ceramic Soci ety 31: 941-976.\n[2] F. Poitrasson\, E. Oelkers\, J. Schott\, J.-M. Monte l\, (2004).Geochimica et Cosmochimica Acta 68: 2207-2221.\n[3] E. Du Fou d e Kerdaniel\, N. Clavier\, N. Dacheux\, O. Terra\, R. Podor\, (2007). Jour nal of Nuclear Materials 362: 451-458.\n[4] N. Dacheux\, N. Clavier\, R. P odor\, (2013). American Mineralogist 98: 833-847.\n[5] C. Gausse\, S. Szen knect\, D.W. Qin\, A. Mesbah\, N. Clavier\, S. Neumeier\, D. Bosbach\, N. Dacheux\, (2016). European Journal of Inorganic Chemistry 2016: 4615-4630. \n[6] S.V. Ushakov\, K.B. Helean\, A. Navrotsky\, L.A. Boatner\, (2001). J ournal of Materials Research 16: 2623-2633.\n[7] D. Qin\, C. Gausse\, S. S zenknect\, A. Mesbah\, N. Clavier\, N. Dacheux\, (2017). The Journal of Ch emical Thermodynamics\, dx.doi.org/10.1016/j.jct.2017.01.003\n\nhttps://ev ents.synchrotron.org.au/event/51/contributions/1130/ URL:https://events.synchrotron.org.au/event/51/contributions/1130/ END:VEVENT BEGIN:VEVENT SUMMARY:(Scholarship application) Thermal Treatment of Magnox Sludge Inter mediate Level Nuclear Waste through Vitrification DTSTART:20171031T003000Z DTEND:20171031T004500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1131@events.synchrotron.org.au DESCRIPTION:Speakers: Claire Corkhill (University of Sheffield)\, Neil Hya tt (The University of Sheffield)\, Sean Morgan (Sellafield Ltd.)\, Adam Fi sher (University of Sheffield)\, Daniel Bailey (University of Sheffield)\, Russell Hand (University of Sheffield)\, Sean Barlow (University of Sheff ield)\n\nVitrification of sludge waste arising from legacy nuclear activit ies such as Magnox reprocessing is a promising alternative to the current baseline plan of cementation with superior long-term durability\, improved waste loadings and significant volume reduction. Glass products were prod uced from oxidized and metallic uranium and magnesium\, representative of the extremes found with the First Generation Magnox Storage Ponds\, in sim ple 3 or 4 component systems. \nMagnesium aluminosilicate (MAS) and magnes ium borosilicate (MBS) glasses were analytically characterised by X-ray di ffraction\, scanning electron microscopy\, differential thermal analysis\, X-ray absorption spectroscopy and inductively coupled plasma optical emis sion spectrometry. Accelerated dissolution testing was performed at 90 °C for 28 days with periodic sampling of the leachate solution. \nSurrogate materials neodymium and the rare-earth alloy mischmetal were used alongsid e uranium and subject to the same testing regime to determine the effectiv eness and validity of using such substitute materials in scientific studie s of uranium bearing glass.\n\nhttps://events.synchrotron.org.au/event/51/ contributions/1131/ URL:https://events.synchrotron.org.au/event/51/contributions/1131/ END:VEVENT BEGIN:VEVENT SUMMARY:Aqueous leaching of high burnup UO2 fuel under hydrogen conditions DTSTART:20171030T043000Z DTEND:20171030T044500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1132@events.synchrotron.org.au DESCRIPTION:Speakers: Kastriot Spahiu (SKB)\, Lena Evins (SKB)\, Olivia Ro th (Studsvik Nuclear)\, Anders Puranen (Studsvik Nuclear)\n\nLeaching resu lts on fragments of high burnup (65 MWd/kgU) UO2 fuel from a commercial pr essurized water reactor are presented. The experiments were performed in s implified granitic groundwater under a hydrogen pressure of up to 5 MPa\, representing conditions in a water intrusion scenario for a Swedish KBS-3 design spent nuclear fuel repository. The freshly crushed fragments were p re-washed under aerated conditions for 6 days to remove part of the instan t release fraction of the radionuclide inventory and transferred to an aut oclave for leaching under hydrogen conditions. Following an initial releas e of U attributed to dissolution of oxidized phases from the aerated handl ing\, the U concentration decreased to levels of 2-5x10-9 M\, in-line with the solubility of amorphous UO2. The release of radionuclides such as Cs and Sr gradually declined indicating a transition towards inhibition of th e fuel matrix dissolution.\n\nhttps://events.synchrotron.org.au/event/51/c ontributions/1132/ URL:https://events.synchrotron.org.au/event/51/contributions/1132/ END:VEVENT BEGIN:VEVENT SUMMARY:Unusual redox neighborhood in technetium compounds DTSTART:20171102T054500Z DTEND:20171102T060000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1133@events.synchrotron.org.au DESCRIPTION:Speakers: Andrey AFANASIEV (A.N.Frumkin Institute of Physical Chemistry and Electrochemistry of Russian Academy of Sciences)\, Mikhail G RIGORIEV ((A.N.Frumkin Institute of Physical Chemistry and Electrochemistr y of Russian Academy of Sciences)\, Alexander FEDOSSEEV ((A.N.Frumkin Inst itute of Physical Chemistry and Electrochemistry of)\, Konstantin German ( A.N.Frumkin Institute of Physical Chemistry and Electrochemistry of Russia n Academy of Sciences)\n\nTechetium has a great number of oxidation states (usually we say 9 but in fact much\nmore) and is evidently one of the ele ments with the most complicated chemistry. This is\ndue its position in th e center of 4d elements row with 7 electrones available for chemical\nbond ing. One of the very special options complicating technetium chemistry is its ability to\ncluster formation and especially the possibility for Tc cl uster to be reduced by consequtive\naddition of electrones one by one. So the oxidation states of Tc in hydrochloric acid could be\n4+ (in K2TcCl6)\ , 3+ (in [Bu4N]2Tc2Cl8)\, 2.5+ (in K3Tc2Cl8)\, 2+ (in K2Tc2Cl6)\, 11/6+\n( in [Me4N]3Tc6Cl14 and 10/6+ (in [Me4N]2Tc6Cl12). We could imagine the numb er of\nhydroxides that could be formed sturting from these compounds. Anot her option is the\npresence of Tc atoms in different oxidation states with in the same compound (p.e. Tc2Ac42\nwhere Tc3+ and Tc7+ coexist in the one compound. New example is the red pertechnic acid.\nAccording to new synth esis and X ray structure study it contains 4 TcO6 octahedra with\nTc6+\, t hat is usually considered extremely unstable and 16 Tc(VII) tetrahedra ara nged in a\njoint compund [TcVI 4TcVII 1668]·16H2O: a = 11.1743(6)\, b = 1 2.8839(6)\, c = 14.0661(6)\nÅ\, α = 71.128(2)\, β = 69.015(2)\, γ = 74 .340(2)◦\n\, P-1\, Z = 1. Of next extreme interest is\nnew Pu(III)(DMSO) 6[TcO4]3 compound where reducing and oxidizing parts coexist.\n\nhttps://e vents.synchrotron.org.au/event/51/contributions/1133/ URL:https://events.synchrotron.org.au/event/51/contributions/1133/ END:VEVENT BEGIN:VEVENT SUMMARY:Comparison of thermal expansion of Tc and Re salts. DTSTART:20171102T050000Z DTEND:20171102T051500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1134@events.synchrotron.org.au DESCRIPTION:Speakers: Sean Injac (Sydney University)\, Michelle Yu (Sydney University)\, Brendan Kennedy (The University of Sydney)\, Emily Reynolds (Oxford University)\, Frederic Poineau (University of Las Vegas\, Nevada) \, Gordon Thorogood (ANSTO)\n\n99Tc is the most significant long-lived pro duct of uranium fission\, producing the largest fraction of the total long -lived radiation emissions of nuclear waste. Tc 7+ compounds are highly m obile in the environment. Relatively little is known regarding the solid state chemistry of Tc. Recently we studied the structural properties of (N H4)TcO4 (Tc7+) and confirmed that this is isostructural with (NH4)ReO4 ado pting a tetragonal scheelite type structure in space group I41/a. The uni t cell parameters of (NH4)TcO4 are strongly temperature dependent with the structure showing negative thermal expansion along both the a- and c-axis \, albeit at different temperatures This behavior is significantly differ ent to that previously reported for the isostructural oxide (NH4)ReO4\, al though we note that the data for (NH4)ReO4 was collected at much lower res olution. Nevertheless it is clear in the literature that the thermal expa nsion behavior of (NH4)ReO4 is highly anisotropic. Despite the difference in the thermal expansion between what we have observed for (NH4)TcO4 and that described by others for (NH4)ReO4 it is likely that the origin of the anomalous thermal expansion in is the same in both cases\, namely it is a consequence of re-orientation of the ammonium ions in the surrounding cag e of eight oxygen atoms. To verify this for (NH4)TcO4 requires we replace the ammonium cation with another small cation. Therefore we have compare d the thermal behavior of AReO4 with ATcO4 to determine if Re oxides are s uitable surrogates to predict the behavior of Tc oxides and how they may b ehave in the environment.\n\nhttps://events.synchrotron.org.au/event/51/co ntributions/1134/ URL:https://events.synchrotron.org.au/event/51/contributions/1134/ END:VEVENT BEGIN:VEVENT SUMMARY:Alkali technetium oxides and their relation to Tc loading in nucle ar waste glasses DTSTART:20171102T051500Z DTEND:20171102T053000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1136@events.synchrotron.org.au DESCRIPTION:Speakers: Chuck Soderquist (Pacific Northwest National Laborat ory)\, Jamie Wesver (Washington State University)\, John McCloy (Washingto n State University)\n\nBecause of their radioactive nature\, solid technet ium-99 oxides have been rarely studied\, and there is\na dearth of modern spectra and diffraction patterns in the literature. This publication aims to address\nthis by detailing a low-temperature synthesis method for pure\ , crystalline alkali pertechnetates\,\nalong with complete analysis by sta tic and magic-angle-spinning nuclear magnetic resonance\, Raman\,\nneutron diffraction (ND)\, and X-ray absorption spectroscopy (XAS). Insight gaine d from these\nstudies brings a deeper understanding of the periodic chemis try of alkali (Na\,K\,Rb\,Cs) pertechnetates.\nAdditionally\, we report at tempts to make 5- and 6-coordinate pertechnetate compounds of K\, Na\,\nan d Li\, i.e. TcO5 - and TcO6 -. It was found that higher coordinated specie s are very sensitive to\nwater\, and easily decompose into their respectiv e pertechnetates. It was difficult to obtain pure\ncompounds\, but mixture s of the pertechnetate and other phases were frequently found\, as evidenc ed\nby XAS\, ND\, and Raman spectroscopy. Additionally\, we summarize othe r work on Tc loading\nin glasses\, effect on glass structure\, and salt fo rmation in overloaded samples. For glasses\, XAS\nchemometrics based on pr incipal component analysis and linear combination fitting suggests that Tc \nis speciated first as isolated Tc4+\, as Tc content is increased\, there is more Tc7+ which partitions\nfirst to K neighbors then to isolated site s. Preliminary work is reported assessing HTcO4 and related\ncompounds and their relationships to mechanisms of Tc volatility\n\nhttps://events.sync hrotron.org.au/event/51/contributions/1136/ URL:https://events.synchrotron.org.au/event/51/contributions/1136/ END:VEVENT BEGIN:VEVENT SUMMARY:U-rich ceramics for Spent Fuel or Acidic 99Mo Production ILW DTSTART:20171101T023000Z DTEND:20171101T024500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1137@events.synchrotron.org.au DESCRIPTION:Speakers: Dorji Chavara (Australian Nuclear Science and Techno logy Organisation)\, Ian Watson (ANSTO)\, Daniel Gregg (ANSTO)\, Eric R Va nce (ANSTO)\n\nSpent fuel has long been unofficially classified as HLW whi ch is cooled for a few years to allow the dissipation of short-lived fissi on products and then is to be contained in thick-walled Cu or carbon steel containers for deep repository disposal where it is argued that the conta iners will perform immobilisation for ~105 yr. However immobilisation assu mes highly reducing conditions in which UO2 is essentially unreactive and even water-soluble fission products will be contained. The only published engineered waste form for spent UO2 fuel is synroc-F in which the U concen tration is nearly 50 wt.% and the fission products are incorporated in res istate titanate mineral phases. We have tried to extend this concept by ho t isostatic pressing glass-ceramics in which synroc-F constitutes the cera mic phase and the glass furnishes a second phase for fission product immob ilisation and increases the general reactivity. We have also used the same approach for acidic 99Mo production ILW.\n\nhttps://events.synchrotron.or g.au/event/51/contributions/1137/ URL:https://events.synchrotron.org.au/event/51/contributions/1137/ END:VEVENT BEGIN:VEVENT SUMMARY:Tc reduction by bacteria from soda lake DTSTART:20171102T053000Z DTEND:20171102T054500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1138@events.synchrotron.org.au DESCRIPTION:Speakers: Tatiana Khijniak (FRC FUNDAMENTALS OF BIOTECHNOLOGY RAS)\, Inga Zinikovskaya (JINR\, Dubna)\, Alexander Kolokoltsev (A.N.Frumk in Institute of Electrochemistry and Electrochemistry of Russian Academy o f Sciences)\, Svetlana Ostalkevich (FSUE RADON)\, Alexey Safonov ((A.N.Fru mkin Institute of Electrochemistry and Electrochemistry of Russian Academy of Sciences)\, Konstantin German (A.N.Frumkin Institute of Physical Chemi stry and Electrochemistry of Russian Academy of Sciences)\n\nOne of the pr oblematic types of LRW are alkaline wastes generated in some types of spen t\nnuclear fuel reprocessing. Environmental friendly biological techniques of LRW treatment\nare not widespread because of its extremely high salt c ontents and alkalinity usually not\nsuitable for organisms. The aim of thi s work was to explore the use of microorganisms\nfrom extremely alkaline h abitat to process liquid alkaline radioactive waste. This involved a\nsear ch of promising microbial cultures from extremely alkaline lakes of the Ku lunda steppe\,\nwhich composition is close to alkaline wastes. The lake se diments with medium (44-85 g/L)\nand extremely high (300-400 g/L) salt con tent were selected for investigations\; the microbial\nassociations\, whic h capable to reduce radionuclides were received. Experiments on reduction\ nof technetium and uranyl acetate + pertechnetate were performed. The bact eria present in\nthe sediments and sludge of soda lakes reduced pertechnet ate ions in both experiments with\nhigh salinity (2.3 M - 84% technetium r educed) and in experiment with a lower salinity (0.8\nM - 86% technetium r educed) wherein uranium had no competitive effect on the recovery of\ntech netium - in experiments with 1) technetium and 2) with technetium + uranyl acetate\nreduced approx. 84% of pertechnetate. When using the mixed sludg e from lower salt content\nlake the amount of reduced technetium was lower compared to the high salinity - 55-60%.\nThis work was supported by RFBR grant 15-05-08919\n\nhttps://events.synchrotron.org.au/event/51/contributi ons/1138/ URL:https://events.synchrotron.org.au/event/51/contributions/1138/ END:VEVENT BEGIN:VEVENT SUMMARY:Current advances on titanate-based glass-ceramics for actinide imm obilization DTSTART:20171101T024500Z DTEND:20171101T030000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1139@events.synchrotron.org.au DESCRIPTION:Speakers: Rob Aughterson (ANSTO)\, Daniel Gregg (ANSTO)\, Inna Karatchevtseva (ANSTO)\, Linggen Kong (Australian Nuclear Science and Tec hnology Organisation)\, Yingjie Zhang (ANSTO)\n\nGlass-ceramics have attra cted recent attention as they have the advantage of combining the chemical flexibility of glasses with the excellent durability of ceramics\, making them potential waste forms for the immobilization of actinide wastes with processing chemicals. Glass-ceramics based on titanate ceramic phases\, e .g. zirconolite\, pyrochlore and brannerite have been developed at ANSTO. The formations of these titanate dominated glass-ceramics have been demons trated with uranium as proof of concept and plutonium with gadolinium and/ or hafnium as neutron absorbers. This talk will focus on the current advan ces in the field including the formation and crystallization of titanate p hases in glass\, structure and microstructure characterization\, actinide incorporation and actinide valences.\n\nhttps://events.synchrotron.org.au/ event/51/contributions/1139/ URL:https://events.synchrotron.org.au/event/51/contributions/1139/ END:VEVENT BEGIN:VEVENT SUMMARY:Partitioning of Ce\, as a Simulant for Pu\, in a Multiphase Cerami c Nuclear Waste Form DTSTART:20171031T224500Z DTEND:20171031T230000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1140@events.synchrotron.org.au DESCRIPTION:Speakers: Gregory Lumpkin (ANSTO)\, Joel Davis (ANSTO)\, Eric R. Vance (ANSTO)\, Kathryn Spiers (Australian Synchrotron)\, Zhaoming Zhan g (ANSTO)\n\nA multi-phase titanate waste form was synthesized using high temperature sintering in air or Ar with the composition of Ca0.71Y0.088Ce0 .52Hf0.22Ti2Ox. The phase assemblage was investigated as a function of the sintering atmosphere. X-ray diffraction measurements indicated that oxidi zing sintering atmosphere (air) favors the formation of pyrochlore\, where as neutral environment (Ar) promotes the formation of perovskite\, althoug h both sintering atmospheres produced samples containing three phases (pyr ochlore\, perovskite and rutile under air or zirconolite\, perovskite and rutile under Ar). Scanning electron microscope (SEM) analysis revealed tha t Ce is present in perovskite and pyrochlore (or zirconolite)\, but not in rutile. Micro-X-ray-Absorption-Near-Edge-Structure (micro-XANES) measurem ents conducted at the Ce L-edge\, in combination with electron energy loss spectroscopy (EELS)\, showed that Ce4+ prefers to inhabit the pyrochlore (or zirconolite) phase and Ce3+ the perovskite phase. This knowledge is v aluable for the further development of titanate waste forms to immobilize Pu.\n\nhttps://events.synchrotron.org.au/event/51/contributions/1140/ URL:https://events.synchrotron.org.au/event/51/contributions/1140/ END:VEVENT BEGIN:VEVENT SUMMARY:P-31 Nuclear Magnetic Resonance as a Probe of Plutonium Incorporat ion and Radiation Damage in Phosphates DTSTART:20171031T044500Z DTEND:20171031T050000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1149@events.synchrotron.org.au DESCRIPTION:Speakers: Joseph Somers (EC-JRC Karlsruhe)\, Laura Martel (EC- JRC Karlsruhe)\, Eric R Vance (ANSTO)\, Katie Smye (University of Cambridg e)\, Ian Farnan (University of Cambridge)\n\nPlutonium doped YPO4 was prep ared to test the extent of solid solution and the effect of radiation dama ge over several years. Y0.92 238Pu0.08PO4 showed the presence of a Pu subs tituted xenotime phase and a 238PuP2O7 phase by X-ray diffraction (XRD). The 31P magic‑angle spinning nuclear magnetic resonance (MASNMR) spectru m showed peaks for PuP2O7 and peaks assigned to phosphorus coupled to Pu3+ substituted randomly into Y3+ sites. A time series of 31P MASNMR and XRD measurements observed the loss of the reflections due to the 238PuP2O7 pha se in the XRD pattern of the Y0.92238Pu0.08PO4 sample within 4 weeks. The MASNMR spectra obtained at longer times in both the Y0.92 238Pu0.08PO4 an d Y0.96 238Pu0.04PO4 samples showed an additional broadened and shifted 31 P resonance assigned to amorphised xenotime with a chemical shift consiste nt with Q0 orthophosphate. Thus\, the amorphised local structure is assign ed to a predominantly Q0 phosphate arrangement subject to local densificat ion.\n\nhttps://events.synchrotron.org.au/event/51/contributions/1149/ URL:https://events.synchrotron.org.au/event/51/contributions/1149/ END:VEVENT BEGIN:VEVENT SUMMARY:Multinational Waste Repositories: A South Australian Initiative DTSTART:20171030T014500Z DTEND:20171030T020000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1142@events.synchrotron.org.au DESCRIPTION:Speakers: Ashok Kaniyal (Harocon)\, Massey de los Reyes (South Australian Environment Protection Authoirty)\n\nOn the 19th of March 2015 \, the Nuclear Fuel Cycle Royal Commission (NFCRC) was established by the South Australian Government\, and tasked to undertake an independent exami nation into the opportunities and risks for South Australia’s further in volvement in the Nuclear Fuel Cycle. This presentation will review the pro cess\, findings and recommendations delivered by the NFCRC\, with particul ar emphasis on the proposed opportunity for the storage and disposal of in ternational high-level and intermediate-level waste in South Australia and the potential value-add that this could provide on a global scale.\nOutco mes of the State-wide 'KnowNuclear' community consultation program will al so be discussed\, as well as the possible next steps needed in advancing t he South Australian multinational repository concept forward.\n\nhttps://e vents.synchrotron.org.au/event/51/contributions/1142/ URL:https://events.synchrotron.org.au/event/51/contributions/1142/ END:VEVENT BEGIN:VEVENT SUMMARY:Quantification of irradiation induced structural disorder in nucle ar waste-form ceramics with µ-luminescence spectroscopy of lanthanides DTSTART:20171031T051500Z DTEND:20171031T053000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1143@events.synchrotron.org.au DESCRIPTION:Speakers: Lutz Nasdala (Institut für Mineralogie & Kristallog raphie\, University of Vienna\, Austria)\, Mihail Ionescu (ANSTO)\, Gordon Thorogood (ANSTO)\, Gregory Lumpkin (ANSTO)\, Christoph Lenz (ANSTO)\n\nT he investigation of radiation damaged or metamict minerals and their synth etic analogues has increased appreciably over the past two decades\, stimu lated by the potential use of mineral-like ceramics as waste forms for the immobilisation of reprocessed spent nuclear fuel and other radioactive wa ste. In this research field\, however\, a fast and inexpensive technique o perating in the micrometre range may open up new opportunities in the char acterisation of radiation damage.\n\nWe present first results of a heavy-i on (Au) irradiation-study of the important nuclear waste-form matrices zir con (ZrSiO4)\, xenotime-(Y) (YPO4) and zirconolite (CaZrTi2O7). Bulk\, pol y-crystalline ceramics were irradiated with accelerated heavy ions (Au) wi th energies up to 35 MeV. Comparably high heavy-ion energies are chosen to ensure irradiation penetration-depths of 4 - 5 µm accessible to the spat ial resolution of optical confocal spectrometers.\n\nhttps://events.synchr otron.org.au/event/51/contributions/1143/ URL:https://events.synchrotron.org.au/event/51/contributions/1143/ END:VEVENT BEGIN:VEVENT SUMMARY:Ion Beam Irradiation of Ceramic-glass Waste Form at ANSTO DTSTART:20171031T053000Z DTEND:20171031T054500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1144@events.synchrotron.org.au DESCRIPTION:Speakers: Lou Vance (ANSTO)\, Greg Lumpkin (ANSTO)\, Mihail Io nescu (ANSTO)\, Inna Karatchevtseva (ANSTO)\, Alan Xu (ANSTO)\, Daniel Gre gg (ANSTO)\, Linggen Kong (ANSTO)\, Yingjie Zhang (ANSTO)\, Tao Wei (ANSTO )\n\nRadioactive wastes are generated from the entire nuclear fuel cycle f rom mining to the burning of uranium fuel in the nuclear reactors. Pyrochl ore (ABTi2O7) and zirconolite (CaZrTiO7) based glass-ceramics have been be came an immerging candidate waste form matrix and attracted attention as i t combines the process and chemical flexibility of glasses with the chemic al durability of ceramics. It also has a potential ability to immobilize s ome compositionally diverse actinide-rich radioactive wastes\, e.g. pluton ium residue wastes and separated minor actinides. The efforts to evaluate the radiation resistance of the glass-ceramic waste form by ion beam irrad iation have been undertaken using accelerators at ANSTO. This paper report ed ANSTO’s capability and development in this area and gave the results of the irradiation-induced structure modification in the glass-ceramics ir radiated by helium and gold ions.\n\nhttps://events.synchrotron.org.au/eve nt/51/contributions/1144/ URL:https://events.synchrotron.org.au/event/51/contributions/1144/ END:VEVENT BEGIN:VEVENT SUMMARY:Investigating Local Defect Structures in Nuclear Waste Form Materi als DTSTART:20171031T041500Z DTEND:20171031T044500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1145@events.synchrotron.org.au DESCRIPTION:Speakers: Eric O'Quinn (University of Tennessee)\, Raul Paloma res (University of Tennessee)\, Maik Lang (University of Tennessee)\n\nFor the past 30 years\, the development of durable materials for radionuclide immobilization has been central to efforts to dispose of wastes generated by the nuclear fuel cycle. There still exist\, however\, large gaps in th e understanding of fundamental modes of waste form degradation under repos itory conditions. Comprehensive evaluation of waste form performance\, inc luding resistance to corrosion\, requires detailed knowledge of the atomic -scale effects of long-term self-irradiation. We have recently shown that pair distribution function (PDF) analysis of neutron total scattering meas urements can be applied to uniquely characterize radiation effects in a wi de range of waste form materials\, including fluorite-derivative pyrochlor es\, actinide oxides\, and glasses. These measurements allow a detailed an alysis of both cation and anion defect behavior\, and short range order an d disorder\, which is particularly important for the investigation of aper iodic glasses. Recent results have shown complex disordering in pyrochlore s\, and oxygen defect clustering in actinide oxides.\n\nhttps://events.syn chrotron.org.au/event/51/contributions/1145/ URL:https://events.synchrotron.org.au/event/51/contributions/1145/ END:VEVENT BEGIN:VEVENT SUMMARY:A study to develop a new glass formulation for the immobilisation of HLW containing molybdenum and large amounts of sodium. DTSTART:20171031T033000Z DTEND:20171031T034500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1146@events.synchrotron.org.au DESCRIPTION:Speakers: John Longmore (Cera Dynamics Ltd\, Fountain Street\, Stoke-on-Trent\, ST4 2HB\, UK.)\, Michael Ingrams (Sellafield Ltd\, Sella field\, Seascale\, Cumbria\,CA20 1PG\, UK.)\, Rebecca Sparkes (Sellafield Ltd\, Sellafield\, Seascale\, Cumbria\,CA20 1PG\, UK.)\, Katy Spencer (S ellafield Ltd\, Sellafield\, Seascale\, Cumbria\,CA20 1PG\, UK.)\, Michel le Eccles (National Nuclear Laboratory\, Sellafield\, Seascale\, Cumbria\, CA20 1PG\, UK)\, Cath Stephen (National Nuclear Laboratory\, Sellafield\, Seascale\, Cumbria\, CA20 1PG\, UK)\, Mike Harrison (National Nuclear Lab oratory\, Sellafield\, Seascale\, Cumbria\, CA20 1PG\, UK)\, Lisa Hollands (ISL\, Department of Materials Science & Engineering\, University of Shef field\, S1 3JD\, UK.)\, Russell Hand (ISL\, Department of Materials Scienc e & Engineering\, University of Sheffield\, S1 3JD\, UK.)\, Clive Brigden (ISL\, Department of Materials Science & Engineering\, University of Sheff ield\, S1 3JD\, UK.)\n\nA study to develop a new high level waste (HLW) gl ass formulation for waste from the highly active liquor storage (HAL) tank s at Sellafield is described. A likely washout scenario for the tanks at the end of operations involves the use of sodium carbonate as a tank washo ut reagent [1] leading to a high soda wastestream. Titanium is not current ly used in existing HLW formulations in European nuclear waste glasses\, h owever\, literature suggests that titanosilicate glasses can accommodate l arge amounts of sodium [2-4]\, even up to 50 mol% [5]. Following a combi natorial type approach exploring the effects of variation of alumina (Al2O 3)\, boron oxide (B2O3)\, calcium and mixed alkali content in sodium titan osilicate formulations with and without waste simulant (including molybden um and zirconium oxides) and durability assessment\, two promising formula tions are currently being trialled and full product waste simulant contain ing glass being prepared via base glass frit plus waste simulant combinati on. Further durability trials and structural characterisation are also be ing investigated and results will be reported.\n \n1 M. J. Edmo ndson et al.\, "A Methodology for Post Operational Clean Out of a Highly A ctive Facility Including Solids Behaviour"\, 12386\, 2012 (Submitted for t he WM2012 Conference\, Phoenix\, Arizona\, USA).\n2 Hamilton\, E. H. a nd G. W. Cleek (1958). "Properties of sodium titanium silicate glasses” J. Res. Nat. Bur. Standards. 61 (2) 89-94.\n3 Turnbull\, R. C. and W. G. Lawrence (1952). "The role of titania in silica glasses” J. Amer. Cer am. Soc. 35 (2) 48-53.\n4 Strimple\, J. H. and E. A. Giess (1958). "Gl ass formation and properties of glasses in the system Na2O-B2O3-SiO2-TiO2" J. Amer. Ceram. Soc. 41 (7) 231-237.\n5 Washburn\, E. W. and E. N. Bu nting (1934). "Note on phase equilibria in the system Na2O-TiO2." J. Res. Nat. Bur. Standards 12 (2) 239-239.\n\nThis document has been prepared by Clive Brigden as part of collaborative project involving Sellafield Ltd. S ome of the information it contains is owned by Sellafield Ltd or NDA and i s\, or may be\, proprietary or subject to restrictions relating to nationa l security\, commercial or personal obligations. It is submitted to Scient ific Basis for Nuclear Waste Management 2017 meeting for the purposes of p rofessional assessment. It may be copied and distributed as required for t his purpose but no other use may be made of any component owned by Sellafi eld Ltd or NDA without the prior permission of Sellafield Ltd.\n\nhttps:// events.synchrotron.org.au/event/51/contributions/1146/ URL:https://events.synchrotron.org.au/event/51/contributions/1146/ END:VEVENT BEGIN:VEVENT SUMMARY:Chornobyl NPP Cooling Pond: Decommissioning DTSTART:20171030T223000Z DTEND:20171030T224500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1150@events.synchrotron.org.au DESCRIPTION:Speakers: Oleksandr Novikov (SSE Chernobyl NPP)\n\nThe Cooling Pond of Chornobyl NPP (hereinafter referred to as CP) was formed by const ructing an embankment on the flood plain of the Prypiat River\, its area m ade about 22.9 km2\; its water volume making 151 million m3 was calculated for cooling Chornobyl NPP four units in mode of electric power generation .\nWhen CP was operated the water level was maintained up to the design le vel which made 111m of BHS (meters as per the Baltic height system).\nThe average annual water level in CP within its operation was 7 meters higher than the water level in the Prypiat River.\nThe special feature of the Coo ling Pond is its location within the area of Exclusion Zone and Absolute ( Obligatory) Resettlement Zone - the area which was radioactively contamina ted resulting from Chornobyl NPP Unit 4 accident in 1986.\nDue to the redu ction of cooling water demand after termination of the electric power gene ration such a facility is not required any more and now its decommissionin g programme is implemented.\nThe Cooling Pond decommissioning activities c over radiation and ecological monitoring\, namely:\n- radiation conditi on in the surface layer of the atmosphere\;\n- exposure dose rate withi n the dry sections of the Cooling Pond\;\n- radionuclide content in gro undwater\;\n- water level\, radiological and chemical changes of the Co oling Pond water\;\n- the changes of the hydrobiological condition and geobotanical changes.\nThe presentation demonstrates the results of radiat ion and ecological monitoring.\n\nhttps://events.synchrotron.org.au/event/ 51/contributions/1150/ URL:https://events.synchrotron.org.au/event/51/contributions/1150/ END:VEVENT BEGIN:VEVENT SUMMARY:Management of the Radioactive Waste arising from the Decommissioni ng of the WWR-S Research Reactor from IFIN-HH\, Magurele\, Romania DTSTART:20171030T230000Z DTEND:20171030T231500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1151@events.synchrotron.org.au DESCRIPTION:Speakers: Felicia Dragolici (IFIN-HH)\, Adrian Zorliu (IFIN-HH )\, Cristian Dragolici (IFIN-HH)\n\nThe WWR-S research reactor from Nation al Institute for R&D in Physics and Nuclear Engineering Horia Hulubei (IFI N-HH)\, Magurele site\, Romania\, is currently in the year 2 of the phase 3 of the decommissioning project. Big components are cut in small parts to reduce the size for a proper packing and temporary disposal. Segregation is used to separate different type of materials depending on their physica l and chemical properties. After that\, the radioactive waste is accommoda ted in a standard barrel (220L) and send to radiological characterization laboratory before its arrival to the Waste Treatment Plant. High activated /contaminated materials are stored in shielded containers.\nIn Romania\, a ll the radioactive waste coming from decommissioning of the research react or is treated and packed at the Radioactive Waste Management Department (R WMD) and sent for final disposal at the National Radioactive Waste Reposit ory (NRWR) in Baita\, Bihor County.\n\nhttps://events.synchrotron.org.au/e vent/51/contributions/1151/ URL:https://events.synchrotron.org.au/event/51/contributions/1151/ END:VEVENT BEGIN:VEVENT SUMMARY:Radionuclide Sorption Behaviour on Fresh and Aged Cementitious Mat erials: A Comprehensive Database with 25 Elements DTSTART:20171031T061500Z DTEND:20171031T063000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1152@events.synchrotron.org.au DESCRIPTION:Speakers: Lian Wang (SCK)\, Michael Ochs (Arcadis)\, Dirk Mall ants (CSIRO)\n\nCementitious materials are being widely used as solidifica tion/stabilisation and barrier materials for a variety of radioactive wast es. The retention properties result from mineral phases in hydrated cement that (i) possess a high density and diversity of reactive sites for the f ixation of radionuclides through a variety of sorption reactions (surface adsorption\, incorporation and solid-solution formation)\, and (ii) buffer pH in the range 10–13. A quantitative database on the solid/liquid dist ribution behaviour (“sorption database”) of 25 elements (Ag\, Am\, Be\ , C\, Ca\, Cl\, Cs\, H\, I\, Mo\, Nb\, Ni\, Np\, Pa\, Pb\, Pd\, Pu\, Ra\, Se\, Sn\, Sr\, Tc\, Th\, U\, Zr) in hydrated cement systems is established on the basis of a consistent review and re-evaluation of literature data. Effects of geochemical evolution or ageing cements on sorption/incorporat ion processes are explicitly evaluated and quantified. In addition to reco mmended values\, all underlying original experimental data and key experim ental information are provided.\n\nhttps://events.synchrotron.org.au/event /51/contributions/1152/ URL:https://events.synchrotron.org.au/event/51/contributions/1152/ END:VEVENT BEGIN:VEVENT SUMMARY:Investigation of C-14 in the CRUD collected on the coolant filter for safety disposal of radioactive waste containing C-14 (II) –Chemical alternation of ion exchange resin under simulated condition in primary coo lant of PWR – DTSTART:20171102T003000Z DTEND:20171102T004500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1153@events.synchrotron.org.au DESCRIPTION:Speakers: Tetsuro Sakahihara (Shikoku Electric Power Co\,INC)\ , Koichiro Takao (Tokyo Institute of Technology)\, Akira Sakashita (Mitsub ishi Heavy Industries\, LTD)\, Kenichiro Kino (Nucler Development Corporat ion)\, Daisuke Minato (Central Research Institute of Electric Power Indust ry)\, Michihiko Hironaga (Central Research Institute of Electric Power Ind ustry)\, Kotaro Nakata (CRIEPI)\n\nRadiocarbon (C-14) is recognized as a r adionuclide that includes significant impact on public exposure in safety assessment of radioactive waste disposal. Its origin\, generation mechanis m and chemical forms in the wastes are required to be understood for the r easonable and proper safety assessment of the radioactive waste disposal. Some previous studies have reported occurrence of insoluble C-14 in PWR\, and suggested that ion-exchange resin could be its origin. However\, this hypothesis has not been well evidenced yet\, because information about the generation mechanism and chemical form of the insoluble C-14 is still lim ited.\nIn this study\, alternation of the resin under heating and/or irrad iation was investigated to understand the alternation of the resin in PWR. In addition\, characteristics of CRUD on a coolant filter for the actual PWR were compared to those of the heated/irradiated resin. The results sug gested that the insoluble C-14 arises from alternation of the ion-exchange resin.\n\nhttps://events.synchrotron.org.au/event/51/contributions/1153/ URL:https://events.synchrotron.org.au/event/51/contributions/1153/ END:VEVENT BEGIN:VEVENT SUMMARY:Activation energy for parabolic corrosion kinetics of Zircaloy-4 b y consecutive hydrogen measurement at 30 – 80℃ DTSTART:20171030T064500Z DTEND:20171030T070000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1155@events.synchrotron.org.au DESCRIPTION:Speakers: Tsuyoshi Tateishi (Kobelco Research Institute\, Inc. )\, Satoshi Yoshida (Kobe Steel\, Ltd.)\, Osamu Kato (Kobe Steel\, Ltd.)\, Tomofumi Sakuragi (Radioactive Waste Management Funding and Research Cent er)\n\nOn the issue related on a safe disposal of spent fuel claddings is the corrosion and the subsequent gas and radionuclides release. The Zircal oy corrosion under a prospected disposal condition has recently been inves tigated by sensitive hydrogen measurements at 30℃\, and reported that th e kinetics in the rate around nm/y follows the parabolic rate law.\nIn the present work\, an improved equipment to be usable even at higher temperat ures up to 80℃ has been applied for measuring hydrogen gas generated fro m Zricaloy-4 corrosion for 90 days. The Arrhenius relation of the paraboli c rate constants for the corrosion kinetics has showed the activation ener gy of 84.4 ± 8.4 kJ/mol\, the value of which is lower than that for the g eneral pre-transition corrosion under the in-pile temperature above 260℃ (i.e. 113-135 kJ/mol)\, suggesting that simple mass transfer through a th in and firm oxide film is limiting the low temperature corrosion of Zircal oy.\n\nhttps://events.synchrotron.org.au/event/51/contributions/1155/ URL:https://events.synchrotron.org.au/event/51/contributions/1155/ END:VEVENT BEGIN:VEVENT SUMMARY:The Need for Integrating the Back End of the Nuclear Fuel Cycle DTSTART:20171030T004500Z DTEND:20171030T011500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1156@events.synchrotron.org.au DESCRIPTION:Speakers: Peter N. Swift (Sandia National Laboratories)\, Evar isto J. Bonano (Sandia National Laboratories)\n\nThe recognition that the endpoint of spent fuel management practices will be deep geologic disposal of radioactive wastes leads to questions about how alternative options fo r spent nuclear fuel (SNF) management might affect performance of a geolog ic repository. Do some options for SNF management simplify the siting and design of a geologic repository? Do some geologic disposal concepts fav or specific SNF management practices? Do some SNF management options favo r specific geologic disposal concepts? Are some waste forms inherently p referable than others for geologic disposal? Given the historical difficu lty in many nations associated with siting and licensing geologic reposito ries for permanent disposal of SNF and high-level radioactive waste (HLW)\ , are there activities that the spent fuel management community could or s hould undertake today to facilitate future disposal operations?\n\nLong-te rm repository safety is\, in general\, independent of specific treatments of SNF or HLW other that its packaging. However\, multiple aspects of the form in which the waste will be disposed are relevant to repository desig n and performance\, including waste volume\, radionuclide content\, therma l power\, waste package size\, and waste form and package lifetime in a ra nge of geologic environments. Consideration of how these factors impact repository performance suggests that choices made now regarding SNF manag ement may affect future flexibility in repository siting and design.\n\nIn the U.S.\, due to the absence of a final disposal site (since the suspens ion of the Yucca Mountain Project in 2009)\, nuclear utilities have been s toring SNF at their nuclear reactor sites using dual-purpose casks. These casks are large and\, depending on the burn-up of the SNF contained there in\, can also be very hot. This current practice can have significant imp lications for transportation and\, ultimately\, disposal. This paper shal l discuss these implications based on the current U.S. practice and will s uggests ways in which these implications can be addressed.\nThe principal message that we intend to convey is the need for careful planning while im plementing upfront and temporary SNF management practices because of their potential costly implications to transportation and disposal. An integra ted view of the entire back end of the nuclear fuel cycle (interim storage \, transportation\, and disposal) upfront during the planning phases is pa ramount to develop and implement an effective SNF management program. \n\nSandia National Laboratories is a multimission laboratory operated by National Technology and Engineering Solutions of Sandia\, LLC\, a wholly o wned subsidiary of Honeywell International\, Inc.\, for the U.S. Departmen t of Energy’s National Nuclear Security Administration under contract DE -NA-0003525. This abstract is Sandia publication 2017-5723A.\n\nhttps://e vents.synchrotron.org.au/event/51/contributions/1156/ URL:https://events.synchrotron.org.au/event/51/contributions/1156/ END:VEVENT BEGIN:VEVENT SUMMARY:Application of Nuclear Waste Management and Remediation Experience and Lessons Learned DTSTART:20171030T224500Z DTEND:20171030T230000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1157@events.synchrotron.org.au DESCRIPTION:Speakers: William Badger (CH2M)\, Bret Clausen (CH2M)\, Jerry O'Leary (CH2M)\, Jeanne Poling (CH2M)\n\n***Applying Successful Global Pro grams to the International Nuclear Decommissioning Market***\n\nCH2M has s uccessfully managed waste management\, remediation and nuclear decommissio ning programs incorporating both innovations and lessons learned that have broad applicability to upcoming major decommissioning programs throughout Australia and globally. \n\nThis abstract presents an international pers pective\, from CH2M\, on the importance of establishing an integrated wast e management strategy with the decommissioning program to better support t he waste generating projects in minimizing the amount of waste generated a nd more effectively comply with regulatory waste acceptance criteria. The overall success of a nuclear decommissioning program can be dependent on a ccurate waste volume projection\; waste disposal pathway identification an d integration\; waste treatment options identification\; waste characteriz ation\, treatment\, packaging and transportation\; and waste disposal (inc luding low-level disposal cell operations). An integrated Waste Management Strategy is integrated with the decommissioning and demolition activities \; nuclear material management and disposition\; waste retrieval\, treatme nt and disposal\; and environmental remediation activities.\n\nhttps://eve nts.synchrotron.org.au/event/51/contributions/1157/ URL:https://events.synchrotron.org.au/event/51/contributions/1157/ END:VEVENT BEGIN:VEVENT SUMMARY:Characterisation of the UK cement backfill material pre- and post- groundwater leaching experiments DTSTART:20171102T030000Z DTEND:20171102T031500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1158@events.synchrotron.org.au DESCRIPTION:Speakers: Claire Corkhill (University of Sheffield)\, John Pro vis (University of Sheffield)\, Neil Hyatt (University of Sheffield)\, Rit a Vasconcelos (University of Sheffield)\n\nIn the UK\, the volume of inter mediate level waste (ILW) requiring final disposal in a geological disposa l facility\, is almost 450\,000 m3. In one of the UK conceptual scenarios for the geological disposal facility in a high-strength crystalline rock\, the vaults will be backfilled with a cement-based material\, known as Nir ex Reference Vault Backfill (NRVB). This material will provide a physical and chemical barrier to radionuclide release to the environment. Over the expected long lifetime performance of a cementitious backfill material\, N RVB will age and alter\, specifically due to interactions with groundwater . Understanding how these interactions will affect the properties of this material is of crucial importance for the development of a robust safety c ase for the geological disposal facility. We here present the results of a detailed characterisation of NRVB pre- and post- groundwater leaching exp eriments\, using three different types of groundwater (granitic\, clay and saline groundwater)\, as analysed using conventional and advanced (e.g. t omography\, synchrotron XRD) techniques.\n\nhttps://events.synchrotron.org .au/event/51/contributions/1158/ URL:https://events.synchrotron.org.au/event/51/contributions/1158/ END:VEVENT BEGIN:VEVENT SUMMARY:Investigation of C-14 in the CRUD collected on the coolant filter for safety disposal of radioactive waste containing C-14 (I)- C-14 release behavior and thermal decomposition characteristics of crud particles coll ected from the coolant filter of commercial PWR - DTSTART:20171102T001500Z DTEND:20171102T003000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1161@events.synchrotron.org.au DESCRIPTION:Speakers: Toshikazu Waki (Kansai Electric Power Co\, INC)\, Sh intaro Tsuji (Kansai Erectric Power Co\, INC)\, Akira Sakashita (Mitsubish i Heavy Industries)\, Kotaro Nakata (CRIEPI)\, Kenichiro Kino (Nucler Deve lopment Corporation)\n\nIn the safety assessment of radioactive waste repo sitory\, it is important to evaluate the migration behavior of long half-l ife radionuclides in the disposal environment. It was reported that insolu ble C-14 was generated in PWR. However\, the knowledge about the chemical form of C-14 is little.\nIn this study\, particles including C-14 collecte d from the coolant filters in PWR were analyzed by TG/MS to identify the c hemical forms of these particles. In addition\, C-14 in released gases and the residue in TG measurements were also investigated.\nResultantly\, it was revealed that fragments which were considered to be organic compounds derived from the ion-exchange resin were detected from the released gas\, and that majority(>90%) of C-14 inventory were detected in the residue aft er the inert gas heating.\nWhile the chemical forms of C-14 in the residue are not clarified\, it is suggested that insoluble C-14 may exist in the thermo-stable compounds.\n\nhttps://events.synchrotron.org.au/event/51/con tributions/1161/ URL:https://events.synchrotron.org.au/event/51/contributions/1161/ END:VEVENT BEGIN:VEVENT SUMMARY:Structural incorporation of Cm3+ and Pu3+ in phosphate ceramics wi th monazite structure. DTSTART:20171101T003000Z DTEND:20171101T004500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1162@events.synchrotron.org.au DESCRIPTION:Speakers: Dirk Bosbach (Forschungszentrum Jülich GmbH\, Insti tute of Energy and Climate Research - IEK-6: Nuclear Waste Management and Reactor Safety\, Jülich\, Germany)\, Joseph Somers (European Commission\, Joint Research Centre\, 76125 Karlsruhe\, Germany)\, Andreas Wilden (Fors chungszentrum Jülich GmbH\, Institute of Energy and Climate Research - IE K-6: Nuclear Waste Management and Reactor Safety\, 52425 Jülich\, Germany )\, Philippe Raison (European Commission\, Joint Research Centre\, 76125 K arlsruhe\, Germany)\, Andre Cabriani (European Commission\, Joint Research Centre\, 76125 Karlsruhe\, Germany)\, André Rossberg (Helmholtz-Zentrum Dresden-Rossendorf\; The Rossendorf Beamline\, The European Synchrotron Ra diation Facility (ESRF)\, P.O. Box 40220\, 38043\, Grenoble\, France)\, An dreas C. Scheinost (Helmholtz-Zentrum Dresden-Rossendorf\, The Rossendorf Beamline\, The European Synchrotron Radiation Facility (ESRF)\, P.O. Box 4 0220\, 38043\, Grenoble\, France)\, Karin Popa (European Commission\, Join t Research Centre\, 76125 Karlsruhe\, Germany)\, Nina Huittinen (Helmholtz -Zentrum Dresden-Rossendorf\, Institute of Resource Ecology\, Bautzner Lan dstraße 400\, 01328 Dresden\, Germany)\, Yulia Arinicheva (Forschungszent rum Jülich GmbH\, Institute of Energy and Climate Research - IEK-6: Nucle ar Waste Management and Reactor Safety\, Jülich\, Germany)\, Stefan Neume ier (Forschungszentrum Jülich GmbH\, Institute of Energy and Climate Rese arch - IEK-6: Nuclear Waste Management and Reactor Safety\, 52425 Jülich\ , Germany)\n\nPhosphate ceramics with monazite structure are considered as potential waste forms for the conditioning of specific nuclear waste stre ams (e.g. minor actinides and plutonium) due to their outstanding properti es. In this study\, the incorporation of actinides (Cm3+ and Pu3+) into th e monazite structure has been investigated combining X-ray diffraction (XR D) as well as X-ray absorption- (XAS) and time-resolved laser fluorescence spectroscopy (TRLFS). \nThe results demonstrate the incorporation of the actinides on defined lanthanide lattice sites in the monazite ceramics. Fr om TRLFS measurements of Cm-doped (50 ppm) (La\,Gd)PO4 solid solutions\, a decrease of short-range order for the solid solution compositions was obs erved in comparison to the end-members. Additionally\, XAS investigations on pure-phase La1-xPuxPO4 (x = 0.01 – 0.15) solid solutions verify the i ncorporation of plutonium in the +III oxidation state in the monazites. Th e results provide a refined structural insight into mechanisms of actinide incorporation into monazite ceramics and solid solution formation.\n\nhtt ps://events.synchrotron.org.au/event/51/contributions/1162/ URL:https://events.synchrotron.org.au/event/51/contributions/1162/ END:VEVENT BEGIN:VEVENT SUMMARY:Highly porous and stable metal–organic frameworks for uranium ex traction DTSTART:20171101T221500Z DTEND:20171101T223000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1163@events.synchrotron.org.au DESCRIPTION:Speakers: Daniel Meyer (CEA)\, Michael Carboni (CEA)\n\nTransf ormative technologies are needed in order to achieve economic uranium extr action from waste to generate a new fuel or for a safe storage. Metal–or ganic frameworks (MOFs) are a class of hybrid materials composed of organi c bridging ligands coordinated to metal ions or metal ion clusters. The re sult is the formation of a porous crystalline solid that possess adequate stability in aqueous solution for potential application in U extraction. T hese materials can selectively precipitate with a specific metal to extrac t it or they have large pore apertures to facilitate the transport of hydr ated actinide\nions through the interior of the frameworks for the extract ion. In this way pollutants such as actinides can be targeted for selectiv e precipitation as a MOF or bind inside the framework by the ligand. This material can be easily recovered by simple filtration or centrifugation an d actinide can be stored after a thermal treatment of the material to fina lly generate an original strategy to combine extraction and storage.\n\nht tps://events.synchrotron.org.au/event/51/contributions/1163/ URL:https://events.synchrotron.org.au/event/51/contributions/1163/ END:VEVENT BEGIN:VEVENT SUMMARY:Best Practice in the Management of Site Investigations for Geologi cal Disposal Facilities DTSTART:20171102T044500Z DTEND:20171102T050000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1164@events.synchrotron.org.au DESCRIPTION:Speakers: Paul Degnan (Catalystra)\n\nThe disposal of intermed iate- and high-level radioactive waste requires emplacement in suitably en gineered underground facilities in order to ensure an adequate level of is olation and containment for safety and security. We now have several examp les of radioactive waste management organisations who have designed and un dertaken extensive multi-disciplinary site investigation projects to chara cterise environments for waste disposal in geological formations. However\ , many countries requiring such facilities are still to initiate their own investigations. It is therefore timely to compile lessons learnt on the m anagement of site investigations for geological disposal facilities in ord er to support the sharing of knowledge and provide a platform for well-pla nned investigations to be undertaken in the future. Consequently\, this pr esentation identifies important considerations associated with the plannin g and implementation of requirements-driven site investigation projects fo r geological radioactive waste disposal facilities.\n\nhttps://events.sync hrotron.org.au/event/51/contributions/1164/ URL:https://events.synchrotron.org.au/event/51/contributions/1164/ END:VEVENT BEGIN:VEVENT SUMMARY:Alkali tin silicate glass as a wasteform for the immobilisation of plutonium DTSTART:20171031T024500Z DTEND:20171031T030000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1166@events.synchrotron.org.au DESCRIPTION:Speakers: Martin Stennett (University of Sheffield)\, Neil Hya tt (The University of Sheffield)\, Amber Mason (University of Sheffield)\n \nUK stocks of separated civil plutonium are projected to exceed 140 tons at the end of reprocessing. This material may require immobilisation in a proliferation resistant wasteform\, should it prove uneconomic to recycle in MOX fuel. We have investigated and optimised alkali tin silicate glas s compositions for the immobilisation of this stockpile using CeO2 as a Pu O2 surrogate. A remarkable two-fold increase in Ce solubility was achieve d by in-situ reduction of CeO2 to Ce2O3\, as demonstrated by Ce L3 XANES\, through addition of zero valent iron\, which also assisted in reducing th e processing temperature. Preliminary investigation showed this approach to be compatible with Hot Isostatic Pressing\, enabling batchwise processi ng of alkali tin silicate glasses\, which is advantageous from fissile mat erial accountancy and criticality considerations. This work demonstrates the feasibility of an alternative and simple approach to conditioning the plutonium stockpile\, through hot isostatic pressing of a full glass waste form\, potentially compatible with the full envelope of plutonium feedstoc k.\n\nhttps://events.synchrotron.org.au/event/51/contributions/1166/ URL:https://events.synchrotron.org.au/event/51/contributions/1166/ END:VEVENT BEGIN:VEVENT SUMMARY:Effect of platinoid elements on the dissolution of uranium dioxide DTSTART:20171030T053000Z DTEND:20171030T060000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1167@events.synchrotron.org.au DESCRIPTION:Speakers: Renaud Podor (ICSM)\, Claire Lavalette (AREVA NC/BG aval)\, adel mesbah (ICSM Marcoule\, France)\, Laurent Claparede (Universi ty of Montpellier)\, Stéphanie Szenknect (ICSM)\, Théo Cordara (ICSM)\, Nicolas DACHEUX (University of Montpellier)\n\nDissolution or leaching of the spent nuclear fuels (SNF) is a key step either in the field of their r eprocessing or their long-term storage in underground repository. Moreover \, SNF contain a wide variety of fission products including platinoid elem ents (PGM’s) either incorporated in the UO2 matrix\, or present in vario us separated phases for which the specific impact on the overall dissoluti on kinetics has not been yet fully discriminated. In order to answer this question\, several samples doped with 0.6 to 3 mol.% of PGM’s (55 % Ru \ ; 9.6 % Rh \; 35.4 % Pd) were prepared from hydroxide based synthesis [1\, 2]. After conversion then sintering\, the prepared pellets were submitted to multiparametric dissolution tests in various media (0.1 to 4 M HNO3) an d temperatures (25°C to 60°C). The macroscopic description of the dissol ution showed that the normalized dissolution rates were significantly incr eased for UO2 doped with PGM’s compared to pure UO2 used as reference co mpound. This effect was strengthened in less acid media. As instance\, a f actor of 4500 was observed after 175 days of leaching in 0.1M HNO3. Simult aneously\, the dissolution of the pellets was followed in operando by ESEM . The combination of macroscopic and microscopic approaches confirmed the modification of the preponderant mechanism occurring at the solid/liquid i nterface from redox-controlled dissolution in strong nitric acid media to surface-controlled dissolution for less acidic media.\n\n1. Martinez\, J. et al.\, J. Nucl. Mater.\, 462\, 173-181\, 2015\n2. Martinez\, J. et al.\, J. Europ. Ceram. Soc.\, 35\, 4535-4546\, 2015\n\nhttps://events.synchrotr on.org.au/event/51/contributions/1167/ URL:https://events.synchrotron.org.au/event/51/contributions/1167/ END:VEVENT BEGIN:VEVENT SUMMARY:Impact of lanthanide elements on the dissolution of uranium dioxid e DTSTART:20171030T041500Z DTEND:20171030T043000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1169@events.synchrotron.org.au DESCRIPTION:Speakers: Renaud Podor (ICSM)\, Claire Lavalette (AREVA NC / B G aval)\, adel mesbah (ICSM Marcoule\, France)\, Stéphanie Szenknect (ICS M)\, Laurent Claparede (University of Montpellier)\, Theo Cordara (ICSM)\, Nicolas DACHEUX (University of Montpellier)\n\nDue to the concomitant for mation of oxygen vacancies in the fluorite structure\, it was found that t he incorporation of trivalent lanthanide elements in ThO2 or CeO2 strongly affect their chemical durability during dissolution or leaching tests [1- 4]. On the contrary\, the impact of such elements on the dissolution of UO 2 remains largely unknown. For this purpose\, several lanthanide – urani um mixed based samples incorporating 1 to 20 mol.% of a mixture of lanthan ide elements (with the mole ratio : 13 % La \; 7.4 % Y \; 25.6 % Ce \; 12 % Pr \; 42 % Nd) were prepared through quantitative oxalate precipitation. After conversion to the final oxides then sintering\, they were character ized from chemical and microstructural points of view and finally submitte d to multiparametric dissolution tests in several nitric acid solutions an d at various temperatures. Contrarily to Th- and Ce-based mixed oxides\, t he presence of lanthanide elements in UO2 did not affect significantly the normalized dissolution rates in concentrated nitric acid solutions (C > 1 M). On the contrary\, the effect was more important in less concentrated s olutions (e.g. a factor or 100 compared to pure UO2 observed in 0.5M HNO3) when the role of surface-controlling reactions on the overall dissolution become predominant. Such observations related to the macroscopic descript ion of the dissolution were connected to in operando following of the evol ving solid/liquid interface that underlined the preferential dissolution o f lanthanide enriched grain boundaries and triple junctions.\n \n1. Horlai t\, D. et al.\, Inorg. Chem.\, 51\, 3868-3878\, 2012\n2. Horlait\, D. et a l.\, J. Nucl. Mater.\, 429\, 237-244\, 2012\n3. Horlait\, D. et al.\, J. M ater. Chem. A\, 2\, 5193-5203\, 2014\n4. Claparede\, L. et al.\, Inorg. Ch em.\, 50\, 11702-11714\, 2011\n\nhttps://events.synchrotron.org.au/event/5 1/contributions/1169/ URL:https://events.synchrotron.org.au/event/51/contributions/1169/ END:VEVENT BEGIN:VEVENT SUMMARY:Development of solid state MAS NMR techniques for the characteriza tion of alteration products formed during the dissolution of spent nuclear fuel. DTSTART:20171030T044500Z DTEND:20171030T050000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1170@events.synchrotron.org.au DESCRIPTION:Speakers: Ian Farnan (Department of Earth Sciences\, Universit y of Cambridge)\, Robert J. Baker (Trinity College\, Dublin)\, Beng Thye T an (University of Cambridge\, Singapore Nuclear Research and Safety Initia tive)\n\nThe migration of radionuclides from underground nuclear waste rep ositories will involve the formation of uranium secondary minerals when gr ound water reacts with the spent nuclear fuel. \n\nDuring oxic or anoxic s pent fuel dissolution\, amorphous phases can precede the development of we ll-defined crystalline mineral phases. Nuclear magnetic resonance (NMR) c an probe the structure of these amorphous alteration products and trace th e evolution of secondary phases. \n\nTo develop the technique\, potential secondary phases of $^{17}$O-enriched uranium minerals have been fabricate d to establish the oxygen environments of becquerelite\, Ca(UO$_2$)$_6$O$_ 4$(OH).8(H$_2$O)\, andersonite\, Na$_2$Ca(UO$_2$)(CO$_3$)3.6H$_2$O and gri mselite\, K$_3$Na(UO$_2$)(CO$_3$)$_3$.(H$_2$O). These contain calcium (Ca$ ^2+$)\, carbonate (CO$_3$$^{2+}$)\, and other ubiquitous ions. \nSolid sta te $^{17}$O MAS-NMR spectra of uranium minerals have been obtained in a 9. 39T magnetic field.\n\n Detailed differences in oxygen local environments such as uranyl bond lengths and interlayer OH and H$_2$O can be distinguis hed by analyzing the spectra\, which can elucidate the alteration of UO$_2 $ by $^{17}$O water.\n\nhttps://events.synchrotron.org.au/event/51/contrib utions/1170/ URL:https://events.synchrotron.org.au/event/51/contributions/1170/ END:VEVENT BEGIN:VEVENT SUMMARY:Simplified UK Magnox waste glass alteration layer characterisation using 29Si\, 17O and 25Mg NMR techniques DTSTART:20171031T030000Z DTEND:20171031T031500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1172@events.synchrotron.org.au DESCRIPTION:Speakers: Ian Farnan (University of Cambridge)\, Rui Guo (Univ ersity of Cambridge)\n\nThe magnesium content of UK Magnox waste glass mak es its aqueous durability much poorer than glasses such as SON68\, which d oes not contain Mg. The glass dissolution kinetics is ultimately dependent on the composition/structures of the altered layers(1)\, here we try to e lucidate formation mechanisms.\n\nAlteration layers formed by in-situ prec ipitation have been discussed widely(2\,3)\, but any direct identification of precipitated phases is not yet known. The altered layers of simplified Magnox waste glasses were examined using a variety of 17O\, 25Mg and 29Si solid-state NMR techniques. In terms of quantification and species identi fication\, the Mg containing glass incorporates 3-4 times the amount of 17 O derived from the 17O enriched leachate compared with a Ca glass\, identi fied as bridging oxygen and hydroxyl oxygen species. At least two types of amorphous surface phases were characterised by proton cross-polarisation (CP) that show local environments similar to clay mineral phases(4). 25Mg and 29Si NMR spectra corroborate the active chemical role of Mg in precip itation and the multiphase nature of the alteration layer.\n\n\n\n 1. Curt i\, E. et al. (2006) Applied Geochemistry 21 pp. 1152-1168\n 2. Geisler\, T (2010) Journal of Non-Crystalline Solids 356 pp. 1458-1465\n 3. Hellmann \, R (2015) Nature Materials 14 pp. 307-311\n 4. Thien\, B. et al. (2010) Applied Clay Science 49 pp. 135-141\n\nhttps://events.synchrotron.org.au/e vent/51/contributions/1172/ URL:https://events.synchrotron.org.au/event/51/contributions/1172/ END:VEVENT BEGIN:VEVENT SUMMARY:Status of Used Nuclear Fuel and Radioactive Waste Long-term Manage ment Programs in Canada DTSTART:20171030T001500Z DTEND:20171030T004500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1173@events.synchrotron.org.au DESCRIPTION:Speakers: Miklos Garamszeghy (Nuclear Waste Management Organiz ation)\n\nIn Canada\, used CANDU (CANada Deuterium Uranium) nuclear fuel f rom the operation of 22 current and former nuclear power reactors\, as wel l as several prototype and demonstration reactors\, is stored in water-fil led pools for about seven to ten years before it is transferred to license d dry storage containers at the nuclear reactor sites. Although safe\, thi s storage practice requires continuous institutional controls such as secu rity\, safeguards\, monitoring and maintenance. \n\nIn November 2002\, th e Canadian Parliament passed the Nuclear Fuel Waste Act (NFWA). It require d the major owners of used nuclear fuel in Canada to establish the Nuclear Waste Management Organization (NWMO). The initial phase of the mandate wa s to perform a three year study of suitable approaches for the safe\, long -term management of used nuclear fuel\, and to recommend a preferred appro ach to the Government of Canada. The study\, which included extensive dia log across Canada with elected officials\, specialists and the general pub lic\, was completed and the report with a recommendation was submitted to the Government in November 2005.\n\nIn June 2007\, the Government of Canad a approved the recommended Adaptive Phased Management (APM) approach. It is consistent with long-term management best practices adopted by other co untries with nuclear power programs. The NWMO was given the mandate to im plement APM.\n\nAPM is both a technical method and a management system. Th e end point of the technical method is the centralized containment and iso lation of Canada's used fuel in a Deep Geological Repository (DGR) in an a rea with suitable geology and an informed and willing host community. APM also involves the development of a transportation system to move the used fuel from the facilities where it is currently stored to the new site.\nTh e management system involves realistic\, manageable phases\, each marked b y explicit decision points. It allows for flexibility in the pace and mann er of implementation\, and fosters the sustained engagement of people and communities throughout its implementation.\n\nAPM is also designed to meet rigorous safety standards throughout all aspects of its design and implem entation. As per this approach\, the used fuel will be isolated and contai ned in a DGR located in a stable crystalline or sedimentary rock formation at a nominal depth of 500 m below ground surface in a willing and informe d host community.\n\nThe DGR concept contains multiple engineered barriers to safely contain and isolate the used fuel over the long-term. The geosp here enclosing the repository provides a natural barrier to protect the wa ste form and EBS\, and to mitigate repository releases at time frames rele vant to repository safety.\n\nThis presentation focusses on the current st atus of the APM program but will also briefly discuss the status of other long-term radioactive waste management activities in Canada.\n\nhttps://ev ents.synchrotron.org.au/event/51/contributions/1173/ URL:https://events.synchrotron.org.au/event/51/contributions/1173/ END:VEVENT BEGIN:VEVENT SUMMARY:Advanced Materials and Processes for Application to the Back-end o f the Nuclear Fuel Cycle DTSTART:20171101T213000Z DTEND:20171101T220000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1174@events.synchrotron.org.au DESCRIPTION:Speakers: Vittorio Luca (Comisión Nacional de Energía Atómi ca)\n\nThe nuclear industry generates a wide variety of radioactive waste streams during reactor operations and maintenance and in virtually all par ts of the fuel cycle. In order to improve the sustainability of the indust ry it is necessary to develop improved methods and processes for treating\ , conditioning and disposing of this waste. The talk will provide an overv iew of research being conducted at the Comisión Nacional de Energía Ató mica emphasizing the development of novel solid-extractants with the abili ty to selectively extract radionuclides from complex solutions and with co mpositions that facilitate end-of-life management by being able to be conv erted to extremely stable ceramics. Topics to be covered will include 1) a proposed process for the conversion of spent polymeric ion exchange resin s to stable pyropolymer and carbon materials and their subsequent immobili zation\, 2) synthesis of coordination polymers suitable for the selective extraction of radiolanthanides and their subsequent immobilization\, 3) po tential new targets for a cleaner production of Mo-99 and 4) the use of ph enolic resins as matrices for spent organic and inorganic ion exchange med ia.\n\nhttps://events.synchrotron.org.au/event/51/contributions/1174/ URL:https://events.synchrotron.org.au/event/51/contributions/1174/ END:VEVENT BEGIN:VEVENT SUMMARY:Radioactive Iodine-129 Capture in Mixed Cation Sodalites: ab initi o modelling DTSTART:20171101T050000Z DTEND:20171101T051500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1179@events.synchrotron.org.au DESCRIPTION:Speakers: Eric R Vance (ANSTO)\, Daniel Gregg (ANSTO)\, Gregor y Lumpkin (ANSTO)\, EUGENIA KUO (Australian Nuclear Science and Technology Organisation)\n\nSodalites have been investigated experimentally for the capture and long-term containment of iodine-129\, a significant and hazard ous waste product of the nuclear fuel cycle. Sodalites are zeolite-type st ructures commonly occurring in nature in alkaline igneous rocks and having the prototype formula Na$_8$(AlSiO$_4$)$_6$Cl$_2$. The crystal structure is based around $\\beta$-cages consisting of corner-sharing SiO$_4$ and Al O$_4$ tetrahedra. In the centre of the $\\beta$-cage is an anion X. Iodine captured by sodalites sits in the centre of the $\\beta$-cages as iodide anions. Silver iodide (AgI) plays an important role in the capture and sub sequent processing of iodine-129 in the nuclear fuel cycle. Using *ab init io* density functional theory (DFT) modelling\, we investigate the energet ics and feasibility of iodine capture and containment in mixed cation soda lites Na$_{8-x}$Ag$_x$(AlSiO$_4$)$_6$I$_2$\, and compare the results with experimental observations.\n\nhttps://events.synchrotron.org.au/event/51/c ontributions/1179/ URL:https://events.synchrotron.org.au/event/51/contributions/1179/ END:VEVENT BEGIN:VEVENT SUMMARY:Functionalised Titania and Zirconia Materials for Selective Actini de and Lanthanide Separations DTSTART:20171101T224500Z DTEND:20171101T230000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1180@events.synchrotron.org.au DESCRIPTION:Speakers: Tracey L. Hanley (ANSTO)\, Vittorio Luca (CNEA)\, Ka trina A. Jolliffe (University of Sydney)\, Jessica Veliscek Carolan (ANSTO )\n\nActinides and lanthanides are targets for partitioning from solutions of spent nuclear fuel. Traditionally\, actinide separation processes are based on liquid-liquid extraction. However\, use of solid phase sorbent ma terials has several advantages such as the lack of organic solvent wastes. Framework materials based on titania and zirconia have been developed and functionalised with organic ligands in order to impart selectivity. Titan ia and zirconia based framework materials were chosen due to their radioly tic and hydrolytic stability\, as well as the fact they can be easily conv erted to transmutation matrices or wasteforms once they are loaded with ac tinides. The framework materials used vary in complexity from simple nanop articles to millimetre sized\, spherical\, hierarchically porous beads. In terms of organic ligands\, functionalisation with phosphonates\, amines a nd bistriazinylpyridine (BTP) has been performed to impart selectivity for lanthanides\, uranium or minor actinides.\n\nhttps://events.synchrotron.o rg.au/event/51/contributions/1180/ URL:https://events.synchrotron.org.au/event/51/contributions/1180/ END:VEVENT BEGIN:VEVENT SUMMARY:The Fabrication and Characterisation of Novel Complex Ceramic Oxid es (Ln2TiO5) For Polyphase Ceramic Waste-Forms. DTSTART:20171031T230000Z DTEND:20171031T231500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1181@events.synchrotron.org.au DESCRIPTION:Speakers: Julie Cairney (University of Sydney)\, Katherine Smi th (ANSTO)\, Gregory Lumpkin (ANSTO)\, Robert Aughterson (ANSTO)\n\nThe st ructure types within the Ln2TiO5 (Ln = lanthanides) system have similariti es with many of the proposed phases within the titanate ceramic waste-form Synroc. Certain compounds might also be suitable for inert matrix fuel ap plications. Previous studies have shown a relationship between lanthanide radii and polymorph type for the Ln2TiO5 system. By using multiple lanthan ides the average lanthanide radius can be controlled and so the structure. In this study four different combinations of lanthanide titanates were fa bricated with the aim of producing single phase\, novel design materials w ith cubic symmetry. Whilst it is possible to fabricate homogeneous materia ls with the general Ln2TiO5 stoichiometry using multiple lanthanides there appears to be limited solubility. The ratio of the lanthanides influences the final structure type and also the solubility. The structure type infl uences the heavy ion irradiation response of these compounds and we report on TEM in-situ experimental results related to this.\n\nhttps://events.sy nchrotron.org.au/event/51/contributions/1181/ URL:https://events.synchrotron.org.au/event/51/contributions/1181/ END:VEVENT BEGIN:VEVENT SUMMARY:Synthesis and Structure of Novel Oxide Compounds Containing RE = Y \, Yb\, Gd\, Sm\, and La and M = Zr\, Ti\, and Sn DTSTART:20171031T220000Z DTEND:20171031T221500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1182@events.synchrotron.org.au DESCRIPTION:Speakers: Robert Aughterson (ANSTO)\, Robin Newman (Imperial C ollege\, London\, UK)\, Greg Lumpkin (ANSTO)\n\nWith the aim of creating n ovel ceramics with high radiation tolerance and ionic mobility\, multiple samples with A-B-O stoichiometries ranging from 215 to 227 were synthesize d and characterized by a combination of SEM\, XRD\, and TEM methods. Singl e-phase defect-fluorite-type compounds with A = Sm or Yb and B = Ti\, Zr\, and/or Sn are reported\; whereas\, pyrochlore compounds were also found a s a second major RE-phase in numerous samples. We describe some interestin g TEM data showing selected area diffraction patterns with complex modulat ions. The details of the modulation wave vectors observed in these samples are reported in some detail. The use of ionic radii to predict the struct ure of these ceramics appears to be substantially limited by Sn-O bonding characteristics and somewhat limited for zirconate compounds. Some single phase ceramics were irradiated with a low dose of helium and no significan t radiation damage was observed by comparative GIXRD and nano-indentation. \n\nhttps://events.synchrotron.org.au/event/51/contributions/1182/ URL:https://events.synchrotron.org.au/event/51/contributions/1182/ END:VEVENT BEGIN:VEVENT SUMMARY:Ambient-Cured Geopolymers for Low Level Nuclear Waste Storage DTSTART:20171031T060000Z DTEND:20171031T061500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1183@events.synchrotron.org.au DESCRIPTION:Speakers: Pramod Koshy (UNSW Sydney)\, Eric Lou Vance (ANSTO)\ , Daniel Gregg (ANSTO)\, Charles C Sorrell (UNSW Sydney)\, Supphatuch Ukri tnukun (UNSW Sydney)\, Isadora Borba da Busch (UNSW Sydney)\n\nRadioactive materials are used for several key applications in Australia\, and result antly\, ~4248 m3 of low level and 656 m3 of intermediate level waste are c urrently stored on site. The present work investigates the development of an ambient-cured geopolymer composition for storage of low level radioact ive wastes. These geopolymers were fabricated by ambient curing of mixtur es of fly ash and blast furnace slag with an alkaline activator. Samples were fabricated both with sand (mortar) and without sand (paste). The cur ed compositions (25x25x25 mm3 cubes showed high compressive strengths of ~ 100 MPa. Microstructural and mineralogical characterisation was conducted using scanning electron microscopy and X-ray diffraction analysis. The s amples will be subjected to gamma irradiation to simulate exposure from in corporated Cs-137 for a few hundred years at ANSTO. Samples will be remov ed at different time points (1-12 months) and microstructural and mechanic al testing will be done to assess its stability.\n\nhttps://events.synchro tron.org.au/event/51/contributions/1183/ URL:https://events.synchrotron.org.au/event/51/contributions/1183/ END:VEVENT BEGIN:VEVENT SUMMARY:Behaviour of sand-bentonite buffer material of deep geological rep ository under high confining pressure DTSTART:20171102T033000Z DTEND:20171102T034500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1184@events.synchrotron.org.au DESCRIPTION:Speakers: Takeshi Kodaka (Department of Civil Engineering\, Me ijo University\, Japan)\, Janaka J. Kumara (Department of Civil Engineerin g\, Meijo University\, Japan)\n\nDeep geological repositories have been pr oposed as a safe waste management system for high-level radioactive wastes . Sand-bentonite buffer materials are used in engineered barrier system of deep geological facilities thank to their excellent swelling properties. In this research\, volumetric and strength behaviour of sand-bentonite buf fer material under high confining pressures of 1-3MPa were studied using a newly developed double-cell triaxial testing apparatus. The specimens wer e prepared with 30% of sand as proposed for geological repositories in Jap an. The suction behaviour of sand-bentonite specimens were also studied.\n The results indicate that the degree of saturation influences the stre ngth and volumetric behaviour significantly\, which suggests that local gr oundwater flow affects the performance of buffer material upon decommissio ning of a deep geological repository. It also indicates that suction behav ior is significantly affected by the degree of saturation\, although it wa s less affected by confining pressure.\n\nhttps://events.synchrotron.org.a u/event/51/contributions/1184/ URL:https://events.synchrotron.org.au/event/51/contributions/1184/ END:VEVENT BEGIN:VEVENT SUMMARY:New aspects of U(V) chemistry in oxo-materials: from ambient to ex treme conditions DTSTART:20171101T051500Z DTEND:20171101T054500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1185@events.synchrotron.org.au DESCRIPTION:Speakers: Evgeny Alekseev (Forschungszentrum Jülich)\n\nUsing extreme pressure (10GPa/1200°C) we obtained a new modification of U2O5 w ith an extraordinary dense structure. The crystal structure of resulting H P (high pressure)-U2O5 is dramatically differs from ambient pressure polym orph so called delta-U2O5. The structure of HP-U2O5 is more related to the cubic UO2 than to the layered delta-U2O5. Using state of the art ab initi o methods we reveal the stability ranges of both ambient and high pressure forms of U2O5 and demonstrated a potential pathway of phase transition un der pressure.\nIn second case we demonstrated that the pentavalent uranium (U(V)) can be stabilized in [Ln(UVO2)W4O14] (Ln = Nd-Tm and Y) series via aliovalent substitution of Ca2+ cations. We confirmed U(V) stabilization using state of the art methods such as U M4 edge high energy resolution X- ray absorption near edge structure (HR-XANES).Magnetic study reveals low t emperature ordering of 5f1 and 4fn systems. All the phases tend to demonst rate the antiferromagnetic properties with significant difference between pure 5f1 system (Y-beating phase) and 5f1-4fn compounds (Nd-Tm).\n\nhttps: //events.synchrotron.org.au/event/51/contributions/1185/ URL:https://events.synchrotron.org.au/event/51/contributions/1185/ END:VEVENT BEGIN:VEVENT SUMMARY:A New Method for Production of Glass-Y2Ti2O7 Pyrochlore DTSTART:20171101T031500Z DTEND:20171101T033000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1187@events.synchrotron.org.au DESCRIPTION:Speakers: Inna Karatchevtseva (Australian Nuclear Science and Technology Organisation)\, Yingjie Zhang (Australian Nuclear Science and T echnology Organisation)\, Linggen Kong (Australian Nuclear Science and Tec hnology Organisation)\n\nThe actinide immobilisation research group at ANS TO has been investigating pyrochlore glass-ceramics for plutonium immobili sation. A novel method of glass ceramic preparation via a soft chemistry r oute has been designed recently. Significant advantages over a more tradit ional mixed oxide route include removal of the need for an organic solvent in synthesis and milling steps\, and product devoid of potentially defici ent minor phases. Glass-Y2Ti2O7 pyrochlore was fabricated by sintering the mixture of glass precursor powder and (YTi)-composite prepared by a soft chemistry route. XRD and Raman confirmed phase pure pyrochlore crystallize d in-situ in amorphous glass matrix at 1200oC. Pyrochlore formation in gla ss was independent of cooling rates and addition of metal fluorides. Glass matrix was able to accommodate/dissolve small amounts of impurities and t he mean pyrochlore particle size was between 1 and 2 µm in glass.\n\nhttp s://events.synchrotron.org.au/event/51/contributions/1187/ URL:https://events.synchrotron.org.au/event/51/contributions/1187/ END:VEVENT BEGIN:VEVENT SUMMARY:New route for synthesis of Synroc-like ceramic using non-selective sorbent LHT-9 DTSTART:20171101T060000Z DTEND:20171101T061500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1189@events.synchrotron.org.au DESCRIPTION:Speakers: Yuri Demidov (Socium Ltd\, St-Petersburg\, Russia)\, Valery Mararitsa (Socium Ltd\, St-Petersburg\, Russia)\, Sergey Britvin ( Saint-Petersburg State University\, St-Petersburg\, Russia)\, Boris Burako v (V.G. Khlopin Radium Institute (KRI)\, St-Petersburg\, Russia)\, Bella Z ubekhina (researcher\, V.G. Khlopin Radium Institute (KRI)\, St-Petersburg \, Russia)\n\nImmobilization of bulk liquid high level waste (HLW) in Synr oc ceramic is well-known reliable way for final isolation of waste from bi osphere. It is proposed the alternative method of synthesis of titanate Sy nroc-like ceramic. Radionuclide incorporation into crystalline titanate ho st-phases can be provided as a result of direct radionuclide sorption from liquid HLW using non-selective sorbent – layered hydrazinium titanate ( LHT-9). Such an approach allows excluding expensive multi-stage procedure of precursor preparation. The precipitate obtained after sorption can be e asily transformed into Synroc-like ceramic by cold pressing and sintering in air at 1000-1100°. The highly radioactive samples of titanate ceramic loaded with 10 wt.% of real HLW were synthesized and studied at KRI hot-ce ll facility. Chemical durability of these samples was tested using MCC-1 s tatic leach test (in distilled water at 90°C) and the leach rate was foun d to be comparable with Synroc ceramic.\n\nhttps://events.synchrotron.org. au/event/51/contributions/1189/ URL:https://events.synchrotron.org.au/event/51/contributions/1189/ END:VEVENT BEGIN:VEVENT SUMMARY:Inert matrix fuel deployment for reducing the plutonium stockpile in reactors DTSTART:20171101T230000Z DTEND:20171101T233000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1190@events.synchrotron.org.au DESCRIPTION:Speakers: Claude Degueldre (Engineering Department\, Lancaster University\, LA1 4YW\, UK)\n\nAbstract – The 450 reactors operating (No v. 2016) around the world (30 countries) produce about 100 tonnes of pluto nium annually\, in spent fuel. Some amounts are separated through reproces sing. While the recycling of plutonium as MOX fuel derives additional ener gy from this resource\, it does little to address the issue of growing plu tonium inventories. If a political objective is to reduce the amount of pl utonium\, then inert matrix fuel (IMF) provides an option for plutonium de struction. More generally\, the utilization of plutonium in IMF provides f lexibility in balancing the quantity of plutonium\, by enabling the net bu rning of plutonium. This approach is viable in existing cores (Gen II&III) that already utilize MOX fuel. IMF can be used both to manage plutonium i nventories and to contribute to reduce the long-term radiotoxicity of the spent fuel by minor actinide destruction. Some of these IMF materials are also being considered for Gen IV reactors\, because of their advanced perf ormance\, economics\, safety features\, sustainability\, and application t o waste minimization in a closed fuel cycle.\nSeveral promising candidate materials have been identified for both fast and thermal reactors: MgO (m agnesia)\, ZrO2 (zirconia)\, SiC (silicon carbide)\, Zr (alloys)\, ZrN (zi rconium nitride)\; some of these have undergone test irradiations and post irradiation examination. These materials may be used as cylindrical pelle ts\, prismatic designed blocs\, or as micro-spheres utilized as sphere-pac or kernels. They can be utilized at the fuel assembly level as prismatic (vertical or horizontal) set up such as in Light Water Reactors\, Pressure d Heavy Water Reactors or Liquid Metal Fast Reactor\, or\, as spherical su ch as in a High Temperature Gas-cooled Reactor. The fuel itself may be ho mogeneously composed of IMF or heterogeneously loaded with the IMF and ura nium material. The assemblies may be homogeneously or heterogeneously load ed with the IMF\, and the reactor core may be homogeneously or heterogeneo usly loaded with IMF assemblies. These three levels\, i.e. fuel\, assembly and core\, of IMF utilization in LWR are considered within a homogeneous- heterogeneous concept scheme as recently reported in the IMF workshop. Mod elling and testing IMF fuel performance and safety analysis have progresse d. Fabrication methods have also been developed or adapted from existing technologies. System studies have identified strategies for both implement ation of IMF fuel in existing reactors in the shorter term\, as well as in new reactors in the longer term. Finally for the backend the burned IMF s hould be an attractive waste form to dispose or in specific conditions eas y to reprocess.\nThe work to date has established the feasibility of these IMF materials\, and core loadings and reactor strategies for utilizing th ese fuels. Further developments are required before commercial deployment of IMF\, which will require additional resources. Additional in-pile irrad iations have been suggested\, both for normal operating and accident condi tions. Further safety analysis and tests are required. Some development is needed for analysis tools and computer programs. Irradiations in commerci al reactors should be undertaken in a staged approach as soon as possible: segmented rods\, full-length rods\, then lead assemblies. IMF can play a n important role in the future of nuclear power.\n\nhttps://events.synchro tron.org.au/event/51/contributions/1190/ URL:https://events.synchrotron.org.au/event/51/contributions/1190/ END:VEVENT BEGIN:VEVENT SUMMARY:NEW ASPECTS OF THE MECHANISM OF HYDROGEN EFFECT ON SPENT FUEL DISS OLUTION DTSTART:20171030T040000Z DTEND:20171030T041500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1191@events.synchrotron.org.au DESCRIPTION:Speakers: Niklas Hansson (Chalmers University of Technology\, Gothenburg\, Sweden)\, Lovisa Bauhn (Chalmers University of Technology\,Go thenburg\, Sweden)\, Kastriot Spahiu (SKB\, Stockholm\, Sweden and Chalmer s University of Technology\, Gothenburg\, Sweden)\n\nOur experimental data indicate that the hydrogen effect is a complex phenomenon and has severa l aspects. The decomposition of hydrogen peroxide on the surface of SIMFUE L is followed by the reaction of the produced hydroxyl radicals with hydro gen to give water\, or their reaction with H2O2 to give O2. Only a very sm all part of the initial hydrogen peroxide (\n\nhttps://events.synchrotron. org.au/event/51/contributions/1191/ URL:https://events.synchrotron.org.au/event/51/contributions/1191/ END:VEVENT BEGIN:VEVENT SUMMARY:Modelling the Corrosion of Spent Nuclear Fuel Inside a failed Wast e Container DTSTART:20171030T033000Z DTEND:20171030T040000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1192@events.synchrotron.org.au DESCRIPTION:Speakers: James Noel (Western University)\, Zach Qin (Western University)\, Nazhen Liu (Western University)\, David Shoesmith (Western U niversity)\n\nThe internationally accepted approach for the disposal of sp ent nuclear fuel is to seal it in corrosion-resistant metal containers and bury it in a stable deep geologic repository. If containers were to fail\ , and the fuel become exposed to groundwater\, radiolytic corrosion of the fuel could release radionuclides to the groundwater\, the critical first step in their transport into the environment. Two corrosion fronts will ex ist within a failed container\, one on the fuel surface driven by radiolyt ic oxidants and a second on the carbon steel vessel sustained by water red uction. Based on an extensive series of electrochemical\, corrosion and ch emical dissolution studies\, a finite-element based model has been develop ed to determine this evolution in redox conditions and its influence on fu el corrosion. Particular attention will be paid to the influence of hydrog en\, produced radiolytically and by corrosion of the steel container vesse l\, on the corrosion rate.\n\nhttps://events.synchrotron.org.au/event/51/c ontributions/1192/ URL:https://events.synchrotron.org.au/event/51/contributions/1192/ END:VEVENT BEGIN:VEVENT SUMMARY:Thorium incorporation in phosphates matrices: the case of xenotime DTSTART:20171101T004500Z DTEND:20171101T010000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1195@events.synchrotron.org.au DESCRIPTION:Speakers: Nicolas dacheux (Institut de Chimie Séparative de M arcoule\, UMR 5257 CEA/CNRS/UM/ENSCM\, Site de Marcoule\, BP 17171\, 30207 Bagnols-sur-Cèze cedex\, France)\, Janeth Lozano-Rodriguez (HZDR\, Insti tute of Resource Ecology\, the Rossendorf Beamline at ESRF\, P.O. Box 220\ , 38043 Grenoble\, France)\, stéphanie Szenknect (Institut de Chimie Sép arative de Marcoule\, UMR 5257 CEA/CNRS/UM/ENSCM\, Site de Marcoule\, BP 1 7171\, 30207 Bagnols-sur-Cèze cedex\, France)\, nicolas clavier (Institut de Chimie Séparative de Marcoule\, UMR 5257 CEA/CNRS/UM/ENSCM\, Site de Marcoule\, BP 17171\, 30207 Bagnols-sur-Cèze cedex\, France)\, adel mesba h (ICSM Marcoule\, France)\n\nThe management and the conditioning of radwa ste represents a major challenge in the nuclear industry. Therefore a vari ety of host matrices have been studied\, including several phosphate based ceramics.1 They represent promising candidates for the specific condition ing of actinides (III\, IV) owing to their easy way of preparation and hig h chemical durability.2\nThe incorporation of actinides in such phases has been extensively studied through solid-state routes. Thus\, it often requ ires repetitive grinding steps and re-heating to avoid the formation of he terogeneous compounds.3 For such reasons\, the synthesis of target compoun ds in aqueous solution were developed to prepare pure and homogenous phase s. \nIn this study\, a particular attention was paid to the incorporation of tetravalent actinides (Th4+\, U4+) in the zircon structure type through the coupled mixed (An(IV) + SiO4 / Ln(III) + PO4) substitution.\nIn this frame\, solid solutions of Er-xThx(PO4)1-x(SiO4)x were obtained in applica tion of the method developed to prepare pure coffinite (USiO4)\, i.e. hydr othermal conditions at 250°C for 7 days.4 The analysis of the PXRD data s howed the formation of single phases. The structure crystallizes in the zi rcon-type structure (I41/amd group\, tetragonal system) as observed for th e end-members ThSiO4 and ErPO4. From Rietveld refinements\, the formation of a complete solid solution was confirmed in agreement with the Vegard’ s law. A thorough analysis was also carried out by Raman spectroscopy and EXAFS at the Er and Th edges and showed an exciting structural evolution.5 \n\n**References**\n\n1. Dacheux\, N.\; Clavier\, N.\; Robisson\, A. C .\; Terra\, O.\; Audubert\, F.\; Lartigue\, J. É.\; Guy\, C. Comptes Rend us Chimie 2004\, 7 (12)\, 1141-1152.\n2. Dacheux\, N.\; Clavier\, N.\; Podor\, R. American Mineralogist 2013\, 98 (5-6)\, 833-847.\n3. Terra\, O.\; Dacheux\, N.\; Audubert\, F.\; Podor\, R. Journal of Nuclear Materia ls 2006\, 352 (1)\, 224-232.\n4. Mesbah\, A.\; Szenknect\, S.\; Clavier \, N.\; Lozano-Rodriguez\, J.\; Poinssot\, C.\; Den Auwer\, C.\; Ewing\, R . C.\; Dacheux\, N. Inorganic Chemistry 2015\, 54 (14)\, 6687-6696.\n5. Mesbah\, A.\; Clavier\, N.\; Lozano-Rodriguez\, M. J.\; Szenknect\, S.\; Dacheux\, N. Inorg Chem 2016\, 55 (21)\, 11273-11282.\n\nhttps://events.sy nchrotron.org.au/event/51/contributions/1195/ URL:https://events.synchrotron.org.au/event/51/contributions/1195/ END:VEVENT BEGIN:VEVENT SUMMARY:Emulsions as a powerful tool to design silica monoliths able to se lectively uptake radioactive caesium DTSTART:20171101T220000Z DTEND:20171101T221500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1196@events.synchrotron.org.au DESCRIPTION:Speakers: Martin Mayer (Institut de Chimie Séparative de Marc oule (ICSM) / Wilhelm Ostwald Institut fur Physikalische and Theoretische Chemie Universitat Leipzig)\, Cyrielle Rey (Institut de Chimie Séparative de Marcoule (ICSM))\, Najat Talha (Institut de Chimie Séparative de Marc oule (ICSM))\, Alicia Sommer-Marquez (Institut de Chimie Séparative de Ma rcoule (ICSM) / Yachay Tech University)\, Jeremy Causse (Institut de Chimi e Séparative de Marcoule (ICSM) - UMR5257 - CEA Marcoule)\n\nThis work de als with the development of new templating routes to design porous nanostr uctured materials with innovative properties and/or easier to prepare. For example\, we have shown that copper hexacyanoferrate nanoparticles could stabilize High-Internal Phase Emulsions or HIPE (**Mayer et al.\, J. Coll. Int. Sci.\, 2017\, doi.org/10.1016/j.jcis.2017.05.113**) that can be used in a second step as a template for functionalized monoliths. It is of gre at interest considering that these coordination polymers come from Prussia n blue analogues family\, the most effective sorbent for caesium\, and the refore relevant in nuclear decontamination purposes of 137Cs or 134Cs. To be active at oil/water interface and stabilize emulsions\, CuHCF particles have to be modified with a polyelectrolyte\, PDDA. The presence of CuHCF all around the oil droplets of the emulsions makes these particles located all around the macropores inside the final silica monolith due to the fac t that the oil droplets are used as a template and should be therefore emp tied after sol/gel gelification of the emulsions in order to create macrop ores. However\, CuHCF can also be used without any PDDA surface modificati on. In this case\, CuHCF nanoparticles are hydrophilic and remain in the w ater phase of the HIPE. The water outer part of the HIPE is the place wher e sol/gel reactions occur. Therefore\, CuHCF nanoparticles are finally loc ated in the monoliths walls if no PDDA is used. However CuHCF nanoparticle s are still accessible to caesium in this case due to the mesoporosity of the walls because of the use of surfactant in this case to stabilize the H IPE (**Causse et al.\, J. Mater. Chem. A\, 2014\, 2\, 9461**). And finally \, we have also developed a third synthesis route of functionalized silica monoliths with CuHCF\, CoHCF and ZnHCF. In this latter exemple\, the HIPE is prepared only with the metal species\, either Cu or Co or Zn. After th e sol/gel reaction a meso/macroporous silica monoliths containing metal sp ecies is obtained. And finally after an impregnation step with K4[Fe(CN)6] \, the corresponding metal hexacyanoferrate particles precipitate inside t he porosity of the silica monolith (**Sommer-Marquez et al.\, RSC Adv.\, 2 016\, 6\, 73475**).\nThis global study showed that we can play with partic les of interest in order to change their location in the templating soft m atter (HIPE) and therefore inside the final monolith. Results of inorganic materials characterization (N2 adsoprtion/desorption\, SAXS\, SEM\, FTIR) as well as Cs sorption isotherms will be shown.\n\nhttps://events.synchro tron.org.au/event/51/contributions/1196/ URL:https://events.synchrotron.org.au/event/51/contributions/1196/ END:VEVENT BEGIN:VEVENT SUMMARY:Preparation of Ln1-2xCaxThxPO4.nH2O rhabdophane-type as low precur sors to monazite-Cheralite ceramics DTSTART:20171101T001500Z DTEND:20171101T003000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1197@events.synchrotron.org.au DESCRIPTION:Speakers: Nicolas Dacheux (Institut de Chimie Séparative de M arcoule\, UMR 5257 CEA/CNRS/UM/ENSCM\, Site de Marcoule\, BP 17171\, 30207 Bagnols-sur-Cèze cedex\, France)\, Stéphanie szenknect (Institut de Chi mie Séparative de Marcoule\, UMR 5257 CEA/CNRS/UM/ENSCM\, Site de Marcoul e\, BP 17171\, 30207 Bagnols-sur-Cèze cedex\, France)\, Nicolas Clavier ( Institut de Chimie Séparative de Marcoule\, UMR 5257 CEA/CNRS/UM/ENSCM\, Site de Marcoule\, BP 17171\, 30207 Bagnols-sur-Cèze cedex\, France)\, Da nwen Qin (Institut de Chimie Séparative de Marcoule\, UMR 5257 CEA/CNRS/U M/ENSCM\, Site de Marcoule\, BP 17171\, 30207 Bagnols-sur-Cèze cedex\, Fr ance)\, adel mesbah (Institut de Chimie Séparative de Marcoule\, UMR 5257 CEA/CNRS/UM/ENSCM\, Site de Marcoule\, BP 17171\, 30207 Bagnols-sur-Cèze cedex\, France)\n\nMonazite\, i.e. LnPO4 (Ln = La-Gd)\, has been widely s tudied as specific ceramic for the conditioning of trivalent and tetravale nt actinides.1 Owing to its chemical and structural flexibility\, the mona zite allows a variety of possible substitutions following different mechan isms.2 Among them\, the so-called cheralite-family\, i.e. Ln1-2xCaxAnIVxPO 4. In this frame\, the major part of protocols reported in the literature was based on solid-state chemistry routes. However\, this method requires the use of repetitive grinding steps and re-heating of actinide bearing po wders and usually forms heterogeneous compounds in term of cationic distri bution. \nIn this work\, we present an alternative method based on wet che mistry route to prepare thorium-based cheralites. It is based on the initi al precipitation of Ln1-2xCaxThxPO4.nH2O3 low temperature precursors cryst allizing in the rhabdophane type structure (monoclinic\, C2 space group).4 A multiparametric study allowed the determination of the appropriate cond itions to form homogeneous and single phase powders. Then these hydrated p recursors were converted to monazite-cheralite ceramics through thermal tr eatment. A coupled in situ PXRD/TGA allowed the identification of the diff erent dehydration steps before the irreversible stabilization of the chera lite anhydrous compounds.5 Moreover\, since such hydrated phases could als o control the release of radionuclides from the ceramics in the field of u nderground repository\, dissolution and solubility experiments have been f inally carried out.\n\n**References**\n\n1. Dacheux\, N.\; Clavier\, N. \; Podor\, R. American Mineralogist 2013\, 98 (5-6)\, 833-847.\n2. Clav ier\, N.\; Podor\, R.\; Dacheux\, N. Journal of the European Ceramic Socie ty 2011\, 31 (6)\, 941-976.\n3. Qin\, D.\; Mesbah\, A.\; Gausse\, C.\; Szenknect\, S.\; Dacheux\, N.\; Clavier\, N. Journal of Nuclear Materials 2017\, 492\, 88-96.\n4. Mesbah\, A.\; Clavier\, N.\; Elkaim\, E.\; Gaus se\, C.\; Kacem\, I. B.\; Szenknect\, S.\; Dacheux\, N. Crystal Growth & D esign 2014\, 14 (10)\, 5090-5098.\n5. Mesbah\, A.\; Clavier\, N.\; Elka im\, E.\; Szenknect\, S.\; Dacheux\, N. Journal of Solid State Chemistry 2 017\, 249\, 221-227.\n\nhttps://events.synchrotron.org.au/event/51/contrib utions/1197/ URL:https://events.synchrotron.org.au/event/51/contributions/1197/ END:VEVENT BEGIN:VEVENT SUMMARY:Synthesis and characterization of brannerite UTi2O6 DTSTART:20171031T221500Z DTEND:20171031T223000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1198@events.synchrotron.org.au DESCRIPTION:Speakers: Nicolas Dacheux (Institut de Chimie Séparative de M arcoule\, UMR 5257 CEA/CNRS/UM/ENSCM\, Site de Marcoule\, BP 17171\, 30207 Bagnols-sur-Cèze cedex\, France)\, stephanie szenknect (Institut de Chim ie Séparative de Marcoule\, UMR 5257 CEA/CNRS/UM/ENSCM\, Site de Marcoule \, BP 17171\, 30207 Bagnols-sur-Cèze cedex\, France)\, adel mesbah (ICSM Marcoule\, France)\n\nThe share of nuclear energy in order to supply elect ricity continues to increase\, which makes a growing need for more uranium resources. Currently uraninite (UO2) and coffinite (USiO4) are the two mo st abundant and exploited minerals. With the exhausting of these resources \, other minerals are currently considered and are subject to multiple stu dies. Among them brannerite (UTi2O6) represents the third source of tetrav alent uranium on Earth and could be considered for uranium recovery.1 Howe ver\, brannerite is known to be very difficult to dissolve quantitatively even in very aggressive conditions.2 Consequently\, the multiparametric s tudy of dissolution of this phase has to be studied in details.\nIn this w ork\, we first focused on the synthesis of pure brannerite by developing n ew methods of synthesis free from heavy grinding steps in contrary of the alkoxide/nitrate based routes.3 The impact of several parameters were stud ied such as heating temperature of synthesis\, holding time and atmosphere . Therefore a new method was developed based on the preparation of hydroxi des mixture then it direct heating under Ar or N2 atmosphere for 72 hours at 1300°C.\nFinally\, dissolution experiments were carried out under diff erent conditions in order to provide multiparametric expression of the nor malized dissolution rate.\n\n**References**\n\n1. IAEA. Uranium extract ion technology. Technical reports series 1993\, 359\, \n2. Gilligan\, R .\; Nikoloski\, A. N. The extraction of uranium from brannerite – A lite rature review. Minerals Engineering 2015\, 71\, 34-48.\n3. Ringwood\, A . E.\; Kesson\, S. E.\; Reeve\, K. D.\; Levins\, D. M.\; Ramm\, E. J. In R adioactive Forms for the Future\; Lutze\, W.\, Ewing\, R. C.\, Ed.\; 1988\ ; p 233.\n\nhttps://events.synchrotron.org.au/event/51/contributions/1198/ URL:https://events.synchrotron.org.au/event/51/contributions/1198/ END:VEVENT BEGIN:VEVENT SUMMARY:Effect of Carbonate on Lanthanides Migration Behavior in Compacted Bentonite DTSTART:20171102T041500Z DTEND:20171102T043000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1199@events.synchrotron.org.au DESCRIPTION:Speakers: Tatsumi Arima (Kyushu university)\, Yaohiro Inagaki (Kyushu university)\, Noriya Okubo (Kyushu university)\, Yuki Kakoi (Kyush u university)\, Kazuyuki Fuji (Kyushu university)\, Kazuya Idemitsu (Kyush u university)\n\nThe apparent diffusion coefficients of La\, Nd\, Eu\, Dy\ , Er and Lu in compacted bentonites were investigated in various bicarbona te concentration. The apparent diffusion coefficients of lanthanides tende d to decrease with increase of dry density. In the lower bicarbonate condi tions than 0.25 M lanthanum had the largest diffusion coefficient of ca. 1 0-13 m2/s at 1.0 Mg/m3 and diffusion coefficient was small as atomic numbe r becomes big. On the other hand in the higher bicarbonate conditions than 0.25 M Lutetium had the largest diffusion coefficient and diffusion coeff icient was small as atomic number becomes small. Especially Lanthanum and Neodymium had smaller diffusion coefficient than 10-14 m2/s even at 1.0 Mg /m3. Diffusion coefficient of Europium was around 10-13 m2/s at 1.0 Mg/m3 and less influence of bicarbonate concentration. Diffusion coefficient of Lutetium increased from 2 x 10-14 to 10-12 m2/s with bicarbonate concentr ation up to 1.0 M.\n\nhttps://events.synchrotron.org.au/event/51/contribut ions/1199/ URL:https://events.synchrotron.org.au/event/51/contributions/1199/ END:VEVENT BEGIN:VEVENT SUMMARY:Effect of thiosulfate on the SCC behavior of carbon steel welds ex posed to concrete pore water under anoxic conditions DTSTART:20171102T023000Z DTEND:20171102T030000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1200@events.synchrotron.org.au DESCRIPTION:Speakers: ROBERTO GAGGIANO (ONDRAF/NIRAS)\, Sebastien CAES (SC K-CEN)\n\nThe Supercontainer (SC) is the reference concept for the post-co nditioning of vitrified high-level nuclear waste and spent fuel in Belgium . It comprises a prefabricated concrete buffer that completely surrounds a carbon steel overpack. Welding is being considered as a final closure tec hnique of the carbon steel overpack in order to ensure its water tightness . Welding is known to induce residual stresses near the weld zone\, which may lead to an increased susceptibility to stress corrosion cracking (SCC) . In this study\, slow strain rate tests were conducted to study the SCC b ehavior of plain and welded P355 QL2 grade carbon steel exposed to an arti ficial concrete pore water solution that is representative for the SC conc rete buffer environment. The tests were performed at 140°C\, a constant s train rate of 5 × 10-7 s-1 and at open circuit potential under anoxic con ditions. The effect of thiosulfate on the SCC behavior was investigated up to levels of 5.35 mM S2O32- (600 mg L-1).\n\nhttps://events.synchrotron.o rg.au/event/51/contributions/1200/ URL:https://events.synchrotron.org.au/event/51/contributions/1200/ END:VEVENT BEGIN:VEVENT SUMMARY:Effects of Li\, Ca\, Fe\, and B on NaAlSiO4 nepheline crystallizat ion in high level waste glasses DTSTART:20171031T010000Z DTEND:20171031T011500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1201@events.synchrotron.org.au DESCRIPTION:Speakers: Yaquoot Shaharyar (Rutgers University)\, Mostafa Ahm adzadeh (Washington State University)\, Jose Marcial (Washington State Uni versity)\, Ashutosh Goel (Rutgers University)\, Ambar Deshkar (Rutgers Uni versity)\, John McCloy (Washington State University)\n\nOwing to high conc entrations of Al2O3 from dissolved fuel cladding and Na2O from basificatio n of the waste\, about half of the high-level waste by volume at Hanford\, Washington\, USA is rich in both Na and Al. Formulations of high waste-l oading glasses result in lower amounts of SiO2\, which often leads to unde sirable precipitation of nepheline (NaAlSiO4). Nepheline crystallization can be affected by modifiers (Li\, Ca) added to lower viscosity and improv e electrical conductivity of the melt. Also\, B is frequently added to re duce viscosity\, and Fe is present in varying amounts from steel tank corr osion. Given the existence of various natural minerals of the stoichiomet ries (Na\,Li\,Ca0.5)(Al\,Fe\,B)SiO4\, we sought to study the effects of su bstitution in the stoichiometric nepheline glass on the resulting crystall ization. We summarize here several years of work\, including characteriza tion by nuclear magnetic resonance\, vibrating sample magnetometry\, Raman spectroscopy\, thermal analysis\, x-ray diffraction\, electron microscopy \, and electron microprobe.\n\nhttps://events.synchrotron.org.au/event/51/ contributions/1201/ URL:https://events.synchrotron.org.au/event/51/contributions/1201/ END:VEVENT BEGIN:VEVENT SUMMARY:Sodalite waste forms for iodine DTSTART:20171101T044500Z DTEND:20171101T050000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1202@events.synchrotron.org.au DESCRIPTION:Speakers: Junghune Nam (Washington State University)\, Brian R iley (Pacific Northwest National Laboratory)\, Saehwa Chong (Washington St ate University)\, John McCloy (Washington State University)\n\nIodine-129\ , released in the off-gas stream during nuclear fuel reprocessing\, is pro blematic due to its long half-life\, high mobility in the earth’s enviro nment\, incorporation into the human thyroid\, and difficulty in immobiliz ing it using traditional vitrification methods. Iodosodalite (Na8Al6Si6O24 I2) has been considered as to immobilize iodine-129 due to feasibility of synthesis at low temperature (\n\nhttps://events.synchrotron.org.au/event/ 51/contributions/1202/ URL:https://events.synchrotron.org.au/event/51/contributions/1202/ END:VEVENT BEGIN:VEVENT SUMMARY:Porosity distribution in a heterogeneous clay-rich fault core DTSTART:20171102T031500Z DTEND:20171102T033000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1203@events.synchrotron.org.au DESCRIPTION:Speakers: Marja Siitari-Kauppi (University of Helsinki)\, Alex andre Dauzères (Institut de Radioprotection et de Sûreté Nucléaire)\, Pierre Dick (Institut de Radioprotection et de Sûreté Nucléaire)\, Juus o Sammaljärvi (University of Helsinki)\, Ville Nenonen (University of Hel sinki)\n\nFault zones influence the mechanical properties and seismologica l behaviour of the Earth’s crust and also the migration and trapping of sub-surface fluids. In addition to natural processes\, their behaviour has broad implications to issues such as oil and gas production\, the sequest ration of carbon dioxide and the geological disposal of radioactive wastes . \nRecent investigations carried out at the Tournemire Underground Labora tory (URL)\, run by the French Institute for Radiological Protection and N uclear Safety (IRSN) have highlighted heterogeneous fault gouge strengthen ing processes within a small-scale vertical strike slip fault affecting a low-permeability shale. \nThe aim of this project is to determine precisel y\, in an apparently heterogeneous and poorly consolidated brecciated rock \, the porosity variations in and around the different fault gouges and de fine their relationship to chemical and/or mechano-chemical processes.\n\n https://events.synchrotron.org.au/event/51/contributions/1203/ URL:https://events.synchrotron.org.au/event/51/contributions/1203/ END:VEVENT BEGIN:VEVENT SUMMARY:Chemical Durability of Borosilicate Glass-Ceramic High-Level Waste Form in Dilute and Static Conditions DTSTART:20171031T004500Z DTEND:20171031T010000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1204@events.synchrotron.org.au DESCRIPTION:Speakers: Jared Kroll (PNNL)\, Jacob Peterson (PNNL)\, Brian R iley (PNNL)\, James Neeway (Pacific Northwest National Laboratory)\, Matth ew Asmussen (PNNL)\, Jarrod Crum (PNNL)\n\nA borosilicate glass-ceramic wa ste form is being developed to significantly increase waste loading of hig h-level waste relative to single phase glass. The glass-ceramic waste for m is comprised of approximately 70% borosilicate glass\, 20% oxyapatite (X 2Ln8Si6O26)\, and 10% powellite (XMoO4)\, by mass\, where X = alkaline ear th and Ln = lanthanides. Understanding the overall corrosion behavior of the glass-ceramic is complicated because each phase corrodes at a differen t rate and there are matrix effects. Durability of the multiphase waste f orm was investigated with single-pass flow-through and static leach testin g\, but the results were convoluted because elements were present in multi ple phases. In an effort to deconvolute the corrosion process of the full waste form\, additional corrosion testing was performed on the full waste form and individually-synthesized phases (remainder glass\, oxyapatite\, and powellite). Results of these tests are presented and comparisons betwe en the glass-ceramic waste form and individual phases are discussed.\n\nht tps://events.synchrotron.org.au/event/51/contributions/1204/ URL:https://events.synchrotron.org.au/event/51/contributions/1204/ END:VEVENT BEGIN:VEVENT SUMMARY:Advances in conditioning of low and intermediate nuclear waste DTSTART:20171029T224500Z DTEND:20171029T231500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1205@events.synchrotron.org.au DESCRIPTION:Speakers: Rebecca Robbins (International Atomic Energy Agency) \, Miklos (Mike) Garamszeghy (Nuclear Waste Management Organization\, Cana da)\, Michael Ojovan (International Atomic Energy Agency)\n\nRadioactive w aste with widely varying characteristics is generated from the operation a nd maintenance of nuclear reactors\, nuclear fuel cycle facilities\, resea rch facilities and medical facilities and the through the use of radioisot opes in industrial applications. The waste needs to be treated and conditi oned as necessary to provide wasteforms acceptable for safe storage and di sposal. Conditioning of radioactive waste is an important step to prepare waste for long-term storage or disposal and includes the following process es: \n• Immobilization which may or may not also provide volume reduc tion\, including (a) Low temperature processes and (b) Thermal processes\; \n• Containerization for (a) Transport\, (b) Storage\, and (c) Dispo sal\; \n• Overpacking of primary containers (a) Prior to disposal and (b) In a disposal facility as part of disposal process. \nConditioning co nsists of operations that produce a waste package suitable for handling\, transportation\, storage and/or disposal and may be performed for a variet y of reasons including standardization of practices and/or wasteforms\, te chnical requirements for waste stability in relation to a repository desig n or safety case\, technical requirements related to waste transportation\ , societal preferences\, regulatory preferences\, etc. This report aims to give an overview of recent advances in conditioning of low and intermedia te nuclear waste.\n\nhttps://events.synchrotron.org.au/event/51/contributi ons/1205/ URL:https://events.synchrotron.org.au/event/51/contributions/1205/ END:VEVENT BEGIN:VEVENT SUMMARY:Towards a ‘3S toolbox’ for providing safety\, security and saf eguards at geological disposal of high-level radioactive waste and spent f uel DTSTART:20171030T220000Z DTEND:20171030T223000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1207@events.synchrotron.org.au DESCRIPTION:Speakers: Irmgard Niemeyer (Forschungszentrum Jülich GmbH)\n\ nSafety\, security and safeguards aspects regarding the geological disposa l of high-level radioactive waste and spent fuel are usually addressed sep arately. Thus\, apparently different methods and techniques exist for each of the three “S’s”. However\, by identifying both synergies in over lapping methods or techniques and differences in the requirements with res pect to safety\, security and safeguards\, advantage of inherent synergies and conflicting requirements can be taken at the same time. [1]\nThe pape r identifies methods and technologies (a ‘3S toolbox’) that would be b est suited for the holistic consideration of safety\, security and safegua rds provisions. Such a toolbox could include\, first\, measurement techniq ues for spent fuel verification already at the encapsulation plant. Second \, a set of measures based on remote monitoring\, nuclear measurements\, c ontainment and surveillance for application at the encapsulation plant\, t he geological repository and transfers between both. Third\, measures for detecting unauthorized activities\, e.g. the analysis of open source infor mation including satellite imagery\, geophysical monitoring and environmen tal sampling. \n\n[1] Niemeyer\, I.\, Deissmann\, G.\, Bosbach\, D.\, B ridging nuclear safety\, security and safeguards at geological disposal of high-level radioactive waste and spent nuclear fuel\, In: International C onference on the Safety of Radioactive Waste Management\, IAEA-CN-242\, 21 -25 November 2016\, Vienna\, Austria\, Book of Paper\, Session 3d\, p.20-2 4.\n\nhttps://events.synchrotron.org.au/event/51/contributions/1207/ URL:https://events.synchrotron.org.au/event/51/contributions/1207/ END:VEVENT BEGIN:VEVENT SUMMARY:Unique capabilities and methods for analysing nuclear waste form m aterials using ANSTO’s landmark infrastructure DTSTART:20171101T054500Z DTEND:20171101T060000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1209@events.synchrotron.org.au DESCRIPTION:Speakers: Brendan Kennedy (The University of Sydney)\, Helen M aynard-Casely (Australian Nuclear Science and Technology Organisation)\, Z haoming Zhang (ANSTO)\, Maxim Avdeev (Australian Nuclear Science and Techn ology Organisation)\, Helen Brand (Australian Synchrotron.)\, Gabriel Murp hy (University of Sydney)\n\nIn situ investigations of nuclear waste form related materials under extreme conditions are highly desirable for unders tanding and optimising applications of these materials\, however they are often exceedingly challenging from a safety and radiological perspective. As a part of our investigations into actinide materials\, we have develope d a number of novel experimental methodologies which utilize ANSTO’s lan dmark research infrastructure\, the Opal nuclear reactor and Australian Sy nchrotron\, towards examining the behaviour of actinide materials related to nuclear waste forms under extreme conditions. This presentation will hi ghlight some of our successes in advancing the study of actinide and nucle ar materials including\n\n - High temperature in situ redox chemistry of u ranium using X-ray absorption spectroscopy.\n\n - The behaviour of uranium oxides under high pressure ( >6 GPa) using neutron diffraction.\n\n - Hig h temperature studies of thorium oxides using synchrotron X-ray and neutro n diffraction.\n\n - Chemistry of uranium oxides under high purity hydroge n gas reduction and high temperature conditions (1000 °C) using synchrotr on X-ray diffraction.\n\nhttps://events.synchrotron.org.au/event/51/contri butions/1209/ URL:https://events.synchrotron.org.au/event/51/contributions/1209/ END:VEVENT BEGIN:VEVENT SUMMARY:Apparent Diffusion Coefficients Consistent with Sorption Derived B ased on Changes in Depth Profiles of Radiocaesium in Soil Contaminated by the Fukushima Nuclear Accident and Future Prediction of Depth Profile DTSTART:20171102T000000Z DTEND:20171102T001500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1210@events.synchrotron.org.au DESCRIPTION:Speakers: Masato Yoshii (Okayama University)\, Haruo Sato (Oka yama University)\n\nH. Sato and M. Yoshii\, Okayama University\, 3-1-1\, T sushima-naka\, Kita-ku\, Okayama-shi\, Okayama 700-8530\, Japan\n\nThe acc ident at the Fukushima Daiichi Nuclear Power Plant occurred following the Great East Japan Earthquake in March 2011\, and led to the release of vola tile radionuclides (RNs) which were deposited on the surrounding environme nt in the Fukushima prefecture. The authors conducted twice investigations on the depth profiles of RNs in soil at 11 locations in the city of Nihon matsu and the towns of Kawamata and Namie.\nThe apparent diffusion coeffic ients (Da) of Cs-134 and Cs-137 were derived from changes in the depth pro files\, and the distribution coefficients (Kd) also calculated from the re lation with Da. The calculated Kd-values ranged 1E4-1E5 ml/g\, which were consistent with Kd-values (2\,080-61\,000 ml/g) obtained by a batch method . The Da-values of both nuclides were approximately of order 1E-14 m2/s an d movement by diffusion was very slow. Furthermore\, the authors simulated change in the depth profiles of both nuclides for 30 years following the accident.\n\nhttps://events.synchrotron.org.au/event/51/contributions/1210 / URL:https://events.synchrotron.org.au/event/51/contributions/1210/ END:VEVENT BEGIN:VEVENT SUMMARY:Synroc Waste Treatment Plant for fission-based Molybdenum-99 Produ ction DTSTART:20171030T011500Z DTEND:20171030T014500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1211@events.synchrotron.org.au DESCRIPTION:Speakers: Ben Bigrigg (ANSTO)\, Amanda Abboud (ANSTO)\, Nick S cales (ANSTO)\, Mitchell Smith (ANSTO Synroc)\, Eric R Vance (ANSTO)\, Dor ji Chavara (Australian Nuclear Science and Technology Organisation)\, Roha n Holmes (ANSTO)\, Gerry Triani (ANSTO)\n\nA new nuclear medicine facility is being built which will enable ANSTO to meet both domestic and global d emand for Molybdenum-99. Co-located on the site will be an innovative wast e treatment facility that deploys ANSTO’s Synroc technologies\; a waste form tailored for immobilizing all the waste elements and fission products and an integrated process line for converting intermediate level liquid waste into a solid compact via hot isostatic pressing (HIP)\, producing a durable waste form suitable for final disposal. This presentation will pro vide a high-level overview of the program\, including various stages of de velopment that are important in building this first of a kind nuclear wast e treatment plant.\n\nhttps://events.synchrotron.org.au/event/51/contribut ions/1211/ URL:https://events.synchrotron.org.au/event/51/contributions/1211/ END:VEVENT BEGIN:VEVENT SUMMARY:Pyrolysis and Plasma applied to Nuclear ion Exchange Resins Treatm ent DTSTART:20171101T223000Z DTEND:20171101T224500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1212@events.synchrotron.org.au DESCRIPTION:Speakers: raul ariel rodriguez (Gerencia Química\, Comisión Nacional de Energía Atómica\, CAC\, Av. Gral. Paz 1499 (1650) Buenos Air es\, Argentina)\, hernan ariel castro (PNGRR\, CNEA\, CAC\, Av. General Pa z 1499 (1650) Buenos Aires\, Argentina / ECyT\, UNSAM\, Martín de Irigoye n 3100 (1650) San Martín\, Argentina)\, vittorio luca (PNGRR\, CNEA\, CAC \, Av. General Paz 1499 (1650) Buenos Aires\, Argentina)\, hugo luis bianc hi (Gerencia Química\, Comisión Nacional de Energía Atómica\, CAC\, Av . Gral. Paz 1499 (1650) Buenos Aires\, Argentina / ECyT\, UNSAM\, Martín de Irigoyen 3100 (1650) San Martín\, Argentina)\n\nSpent ion exchange res ins (IER) represent an important waste stream that is generated during the operation of both light and heavy-water reactors. Over the past 60 years of nuclear activity Argentina has accumulated over 300 m3 of spent IERs th at to this day remain interim storage. With a view toward achieving a sign ificant volume reduction and improved product stability we are investigati ng a two-step process involving initial low-temperature (\n\nhttps://event s.synchrotron.org.au/event/51/contributions/1212/ URL:https://events.synchrotron.org.au/event/51/contributions/1212/ END:VEVENT BEGIN:VEVENT SUMMARY:Atomistic simulation of interfaces in glass/crystal composites for nuclear waste forms DTSTART:20171101T033000Z DTEND:20171101T034500Z DTSTAMP:20261007T035600Z UID:indico-contribution-1213@events.synchrotron.org.au DESCRIPTION:Speakers: Bill E. Lee (Imperial College London)\, Michael J. D . Rushton (Imperial College London)\, Paul C. M. Fossati (Imperial College London)\n\nHigh-Level Waste (HLW) resulting from fuel reprocessing is imm obilised in a borosilicate glass matrix\, particularly in France and the U K.\nSome HLW components have higher melting points than the glass\, and th us never disolve into the melt.\nOther crystalline phases may also form du ring fabrication due to limited solubility.\nSeparation could also occur l ater through a process of devitrification.\nThe resultant waste form may t herefore demonstrate significant heterogeneity with secondary crystal phas es embedded in a glass matrix.\n\nThe purpose of this study is to improve understanding of the issues associated with such microstructures in vitri fied wasteforms.\nWe will present results from atomistic simulations show ing properties of glass/crystal interfaces in a surrogate composite formed of (Na$_{2}$)$_{x}$(SiO$_{2}$)$_{1-x}$ glass and rutile TiO$_{2}$ crystal s.\nThe potentials employed have been widely used for glass materials. We will discuss their applicability to glass/crystal composite structures.\nW e will show structural and energetic features predicted for these interfac es and consider the effect of radiation damage.\n\nhttps://events.synchrot ron.org.au/event/51/contributions/1213/ URL:https://events.synchrotron.org.au/event/51/contributions/1213/ END:VEVENT BEGIN:VEVENT SUMMARY:Radionuclide containing solid phases on the inner surface of a Zir caloy-4 cladding tube DTSTART:20171030T061500Z DTEND:20171030T063000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1215@events.synchrotron.org.au DESCRIPTION:Speakers: Volker Metz (Karlsruhe Institute of Technology)\, Ro n Dagan (Karlsruhe Institute of Technology)\, Dieter Schild (Karlsruhe Ins titute of Technology)\, Jörg Rothe (Karlsruhe Institute of Technology)\, kathy Dardenne (Karlsruhe Institute of Technology)\, Nikolaus Müller (Kar lsruhe Institute of Technology)\, Michel Herm (Karlsruhe Institute of Tech nology)\, Ernesto González-Robles Corrales (Karlsruhe Institute of Techno logy)\n\nZircaloy claddings of fuel rods for nuclear reactors are consider ed as first technical barrier for retention of radionuclides produced in t he nuclear fuel. The integrity of the cladding is influenced by various pr ocesses during reactor operation and beyond\, e.g. oxidation\, hydrogen up take\, PCI\, fission product precipitation\, -decay\, and radiation dam age. Composition of agglomerates found on the inner surface of the plenum section of an irradiated Zircaloy-4 cladding tube are investigated by SEM- EDX\, XPS\, and synchrotron based techniques.\nµ-XRF investigations show uranium hot spots and fission products. Grooves from cladding tube product ion contain uranium residues from fuel pellets insertion. Plutonium\, cesi um and rubidium are present ibidem. Another type of agglomerates contains cesium\, rubidium\, and minor amounts of actinides. Cesium and rubidium ma y originate from three sources: uranium traces within the cladding\, urani um residues in surface grooves\, and Cs/Rb released from subjacent fuel pe llets.\n\nhttps://events.synchrotron.org.au/event/51/contributions/1215/ URL:https://events.synchrotron.org.au/event/51/contributions/1215/ END:VEVENT BEGIN:VEVENT SUMMARY:Dissolution Behavior of Lead Borate Glass under Simulated Geologic al Disposal Conditions DTSTART:20171031T031500Z DTEND:20171031T033000Z DTSTAMP:20261007T035600Z UID:indico-contribution-1217@events.synchrotron.org.au DESCRIPTION:Speakers: Tomofumi Sakuragi (Radioactive Waste Management Fund ing and Research Center)\, Tamotsu Chiba (JGC Corporation)\, Takahiro Kiku chi (JGC Corporation)\, Toshihiro Kogure (The University of Tokyo)\, Tsuto mu Sato (Hokkaido University)\, Atsushi Mukunoki (JGC Corporation)\n\nLead borate glass vitrified at a low temperature is regarded as one of the pro mising immobilization materials of Iodine-129 which will be removed from a spent AgI filter generated from reprocessing plants and may cause signifi cant effect onto long term safety of geological disposal.\nImmersion tests in various solutions have been conducted to understand glass dissolution behaviors in possible geological disposal conditions. Boron dissolved with the highest rate in all types of the solutions and was regarded as an ind ex element to represent the glass dissolution rate. On the other hand\, le ad dissolved with a far slower rate. Chemical species and the possible pre cipitating minerals of lead were examined by a geochemical calculation cod e for typical underground water. Altered glass surfaces were investigated by SEM\, TEM and XRD. XRD analysis showed that the main constituent phase of the altered layer was hydrocerussite\, Pb3(CO3)2(OH)2 that was predicte d by the geochemical simulation as well\n\nhttps://events.synchrotron.org. au/event/51/contributions/1217/ URL:https://events.synchrotron.org.au/event/51/contributions/1217/ END:VEVENT END:VCALENDAR