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Pyrochemical processes applied to spent nuclear fuel recycling have been studied for more than 70 years but they are still far from any industrial deployment. First an overview of the thermodynamical bases of the molten salt chemistry is presented, relying mainly on redox reactions, controlled by either chemical reagents or the potential of the solution. Then, the key process options are described. Selective precipitation, liquid-liquid reductive extraction, electrorefining and electrowinning are the four potential processes that can be used, sometimes in combination, to define a pyrochemical of spent fuel. A limited number of concepts have been developed at the lab-scale, and less than five at the pilot scale, very often focusing only on the core process. Despite quite simple chemical bases, and potential advantages on the paper, their poor performances for advanced partitioning strategies applied to oxide nuclear fuel cycles have limited their application on fast reactor metallic reactor recycling in a homogeneous mode (all the transuranics together). In particular, the lack of short or mid-terms industrial perspectives has not allowed the design and the demonstration of a whole pyrochemical fuel cycle. The choice of the deployment of fast reactor fleets using metallic fuel could allow such developments.
Stéphane Bourg. The Chemical Basis for Separating Recycling Materials by Pyro-Processes. Encyclopedia of Nuclear Energy 2021, 465 -481.
AMA StyleStéphane Bourg. The Chemical Basis for Separating Recycling Materials by Pyro-Processes. Encyclopedia of Nuclear Energy. 2021; ():465-481.
Chicago/Turabian StyleStéphane Bourg. 2021. "The Chemical Basis for Separating Recycling Materials by Pyro-Processes." Encyclopedia of Nuclear Energy , no. : 465-481.
This article aims at giving an overview on the relative impact of the back-end of the fuel cycle on the overall environmental footprint of nuclear energy. Indeed, fuel cycle back-end is often depicted in media as a very significant contributor to pollution and detrimental environmental impact, although it is not supported by relevant and reliable data. This article depicts how Life Cycle Assessment methodology can allow deriving relevant and scientifically sound indicators of the respective contribution of the various nuclear activities on the overall impact. It describes the relative contribution of the back-end of the nuclear fuel cycle while enlightening the relative low impact of recycling and waste disposing activities. The potential impact of future fuel cycles where recycling would be more widely implemented is assessed based on relevant simulations. Also compared is the overall environmental impact of nuclear energy versus fossil fuel and renewable energy technologies. Nuclear energy features one of the lowest environmental impacts.
Ch. Poinssot; S. Bourg. Assessment of the Relative Environmental Footprint of Nuclear Energy and Its Fuel Cycle. Encyclopedia of Nuclear Energy 2021, 675 -683.
AMA StyleCh. Poinssot, S. Bourg. Assessment of the Relative Environmental Footprint of Nuclear Energy and Its Fuel Cycle. Encyclopedia of Nuclear Energy. 2021; ():675-683.
Chicago/Turabian StyleCh. Poinssot; S. Bourg. 2021. "Assessment of the Relative Environmental Footprint of Nuclear Energy and Its Fuel Cycle." Encyclopedia of Nuclear Energy , no. : 675-683.
Processes such as PUREX allow the recovery and reuse of the uranium and the plutonium of GEN II/GEN III reactors and are being adapted for the recycling of the uranium and the plutonium of GEN IV MOX fuels. However, it does not fix the sensitive issue of the long-term management of the high active nuclear waste (HAW). Indeed, only the recovery and the transmutation of the minor actinides can reduce this burden down to a few hundreds of years. In this context, and in the continuity of the FP7 EURATOM SACSESS project, GENIORS focuses on the reprocessing of MOX fuel containing minor actinides, taking into account safety issues under normal and mal-operation. By implementing a three-step approach (reinforcement of the scientific knowledge => process development and testing => system studies, safety and integration), GENIORS will provide more science-based strategies for nuclear fuel management in the EU.
Stéphane Bourg; Andreas Geist; Jean-Marc Adnet; Chris Rhodes; Bruce C. Hanson. Partitioning and transmutation strategy R&D for nuclear spent fuel: the SACSESS and GENIORS projects. EPJ Nuclear Sciences & Technologies 2020, 6, 35 .
AMA StyleStéphane Bourg, Andreas Geist, Jean-Marc Adnet, Chris Rhodes, Bruce C. Hanson. Partitioning and transmutation strategy R&D for nuclear spent fuel: the SACSESS and GENIORS projects. EPJ Nuclear Sciences & Technologies. 2020; 6 ():35.
Chicago/Turabian StyleStéphane Bourg; Andreas Geist; Jean-Marc Adnet; Chris Rhodes; Bruce C. Hanson. 2020. "Partitioning and transmutation strategy R&D for nuclear spent fuel: the SACSESS and GENIORS projects." EPJ Nuclear Sciences & Technologies 6, no. : 35.
The SCRREEN project gathers more than 50 European initiatives, associations, organisations or independent experts working on Critical Raw Materials (CRM) into a long-lasting network including stakeholders, public authorities, and civil society representatives. SCRREEN contributes to improve the CRM strategy in Europe by (i) mapping primary and secondary resources and substitutes of CRMs, (ii) estimating the expected demand of various CRMs in the future and identifying major trends, (iii) providing policy and technology recommendations for actions improving the production and the potential substitution of CRM, (iv) addressing specific waste electrical and electronic equipment (WEEE) and other End-of-Life (EoL) product issues related to their mapping and treatment standardization, and (vi) identifying the knowledge gathered over previous years and making the data accessible to those beyond the project. As a first step, SCRREEN worked at providing stakeholders with a comprehensive analysis of the current use of the CRM, the mapping of potential primary and secondary resources, and identification of the key technologies used in their production. Substitution profiles, analysis of European business and policy issues pertinent to CRMs, and an identification of the standards, policies, and regulatory frameworks concerning these CRM was also completed. In a second step, to be conducted between mid-2018 and mid-2019, SCRREEN will provide guidance for improving the CRM market in Europe by identifying opportunities from research, development, and innovation (R&D&I) that could reduce the supply and/or economic risks around the most relevant CRM for Europe.
Stéphane Bourg. SCRREEN: Solutions for Critical Raw Materials—A European Expert Network. Proceedings of the International Conference on Martensitic Transformations: Chicago 2018, 2367 -2379.
AMA StyleStéphane Bourg. SCRREEN: Solutions for Critical Raw Materials—A European Expert Network. Proceedings of the International Conference on Martensitic Transformations: Chicago. 2018; ():2367-2379.
Chicago/Turabian StyleStéphane Bourg. 2018. "SCRREEN: Solutions for Critical Raw Materials—A European Expert Network." Proceedings of the International Conference on Martensitic Transformations: Chicago , no. : 2367-2379.
SCRREEN project gathers more than 50 European initiatives, associations, organisations or independent experts working on Critical Raw Materials (CRM) into a long lasting Network including stakeholders, public authorities and civil society representatives. SCRREEN contributes to improve the CRM strategy in Europe by (i) mapping primary and secondary resources (ii) estimating the expected demand of various CRMs and identifying the major trends, (iii) providing policy and technology recommendations for actions improving production and substitution of CRMs, (iv) addressing specific waste electrical and electronic equipment (WEEE) and End-of-Life (EoL) products issues related to their mapping and treatment standardization, and (v) identifying the knowledge gained over the last years and easing the access to these data. In the last months, SCRREEN worked at providing stakeholders with a comprehensive analysis of the current use of CRMs, the mapping of potential primary and secondary resources, an identification of the key technologies used for their production, CRM substitution profiles, an analysis of relevant business for Europe in the field, and an identification of standards, policies and regulatory frameworks concerning CRMs. SCRREEN will also provide guidance for improving the CRM market and policy in Europe.
Giovanni Di Girolamo; Stéphane Bourg. Solutions for Critical Raw Materials Supply: Main Activities in the SCRREEN Project. 2018 IEEE International Conference on Environment and Electrical Engineering and 2018 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I&CPS Europe) 2018, 1 -4.
AMA StyleGiovanni Di Girolamo, Stéphane Bourg. Solutions for Critical Raw Materials Supply: Main Activities in the SCRREEN Project. 2018 IEEE International Conference on Environment and Electrical Engineering and 2018 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I&CPS Europe). 2018; ():1-4.
Chicago/Turabian StyleGiovanni Di Girolamo; Stéphane Bourg. 2018. "Solutions for Critical Raw Materials Supply: Main Activities in the SCRREEN Project." 2018 IEEE International Conference on Environment and Electrical Engineering and 2018 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I&CPS Europe) , no. : 1-4.
In this early 21st century, our societies have to face a tremendous and increasing energy need while mitigating the global climate change and preserving the environment. Addressing this challenge requires an energy transition from the current fossil energy-based system to a carbon-free energy production system, based on a relevant energy mix combining renewables and nuclear energy. However, such an energy transition will only occur if it is accepted by the population. Powerful and reliable tools, such as life cycle assessments (LCA), aiming at assessing the respective merits of the different energy mix for most of the environmental impact indicators are therefore mandatory for supporting a risk-informed decision-process at the societal level. Before studying the deployment of a given energy mix, a prerequisite is to perform LCAs on each of the components of the mix. This paper addresses two potential nuclear energy components: a nuclear fuel cycle based on the Generation III European Pressurized Reactors (EPR) and a nuclear fuel cycle based on the Generation IV Sodium Fast Reactors (SFR). The basis of this study relies on the previous work done on the current French nuclear fuel cycle using the bespoke NELCAS tool specifically developed for studying nuclear fuel cycle environmental impacts. Our study highlights that the EPR already brings a limited improvement to the current fuel cycle thanks to a higher efficiency of the energy transformation and a higher burn-up of the nuclear fuel (−20% on most of the chosen indicators) whereas the introduction of the GEN IV fast reactors will bring a significant breakthrough by suppressing the current front-end of the fuel cycle thanks to the use of depleted uranium instead of natural enriched uranium (this leads to a decrease of the impact from 17% on water consumption and withdrawal and up to 96% on SOx emissions). The specific case of the radioactive waste is also studied, showing that only the partitioning and transmutation of the americium in the blanket fuel of the SFR can reduce the footprint of the geological disposal (saving up to a factor of 7 on the total repository volume). Having now at disposition five models (open fuel cycle, current French twice through fuel cycle, EPR twice through fuel cycle, multi-recycling SFR fuel cycle and at a longer term, multi-recycling SFR fuel cycle including americium transmutation), it is possible to model the environmental impact of any fuel cycle combining these technologies. In the next step, these models will be combined with those of other carbon-free energies (wind, solar, biomass…) in order to estimate the environmental impact of future energy mixes and also to analyze the impact on the way these scenarios are deployed (transition pathways).
Jérôme Serp; Christophe Poinssot; Stéphane Bourg. Assessment of the Anticipated Environmental Footprint of Future Nuclear Energy Systems. Evidence of the Beneficial Effect of Extensive Recycling. Energies 2017, 10, 1445 .
AMA StyleJérôme Serp, Christophe Poinssot, Stéphane Bourg. Assessment of the Anticipated Environmental Footprint of Future Nuclear Energy Systems. Evidence of the Beneficial Effect of Extensive Recycling. Energies. 2017; 10 (9):1445.
Chicago/Turabian StyleJérôme Serp; Christophe Poinssot; Stéphane Bourg. 2017. "Assessment of the Anticipated Environmental Footprint of Future Nuclear Energy Systems. Evidence of the Beneficial Effect of Extensive Recycling." Energies 10, no. 9: 1445.
Each year, more than 10 thousand tons of spent fuels are discharged from nuclear power plants in the world. Heavy element nuclear fission reactions, at the origin of energy production, generate fission products of intermediary mass, some of them being considered nowadays as critical raw materials. The potential interest to treat these spent fuels in order to recycle these elements has risen recently following increasing international tensions on their supply for industry and energy. A study was carried out on the basis of the French nuclear fuel cycle scenario in order first to evaluate the inventory of such metals in spent fuel. The only elements of interest, since in significant amount, would be rare earth elements (REE) and platinum group metals (PGM). However, compare to the annual need of REE, the amount that would be recovered from spent fuels represent less than 0.01% of the annual world production. Because of the low price of these elements, there is no economic interest for such a recovery. The case of PGM, and specifically ruthenium and rhodium, is quite different. Even if a lower amount of these elements are in spent fuel, it represents 22% for Ru and 3.5% for Rh of the annual world production. The drawback is that these elements have numerous radioactive isotopes that forbid using them for industrial applications. 20–50 years of storage after separation would be necessary for ruthenium and rhodium to get a radioactivity level lower than potential clearance levels. Before any industrial use, very efficient separation processes would be required to selectively recover these elements. The physico-chemical forms of these elements in the spent fuel make the work tricky. Finally, such a use would require the official existence of a clearance level for nuclear materials as recommended by the IAEA
Stéphane Bourg; Christophe Poinssot. Could spent nuclear fuel be considered as a non-conventional mine of critical raw materials? Progress in Nuclear Energy 2017, 94, 222 -228.
AMA StyleStéphane Bourg, Christophe Poinssot. Could spent nuclear fuel be considered as a non-conventional mine of critical raw materials? Progress in Nuclear Energy. 2017; 94 ():222-228.
Chicago/Turabian StyleStéphane Bourg; Christophe Poinssot. 2017. "Could spent nuclear fuel be considered as a non-conventional mine of critical raw materials?" Progress in Nuclear Energy 94, no. : 222-228.
This paper describes the anticipated long-term evolutions of nuclear fuel cycles. The main driver for such an evolution is the need for improving the sustainability of global energy systems. Indeed, sustainability is becoming the international reference approach to reconciling the different fields of analysis, i.e. the technical performance, economic viability, environmental preservation and societal acceptance. While our societies have to face the issue of finding new energy models which help to mitigate climate change, global approaches are mandatory to select the relevant improvements for the different energy systems, including nuclear energy. In a first step, this paper focuses on the specific environmental footprint of nuclear energy and its position with regards the other energy sources. From this situation, this paper depicts the potential improvement to be studied in order to improve the overall environmental footprint.
Ch. Poinssot; Stéphane Bourg; B. Boullis. Improving the nuclear energy sustainability by decreasing its environmental footprint. Guidelines from life cycle assessment simulations. Progress in Nuclear Energy 2016, 92, 234 -241.
AMA StyleCh. Poinssot, Stéphane Bourg, B. Boullis. Improving the nuclear energy sustainability by decreasing its environmental footprint. Guidelines from life cycle assessment simulations. Progress in Nuclear Energy. 2016; 92 ():234-241.
Chicago/Turabian StyleCh. Poinssot; Stéphane Bourg; B. Boullis. 2016. "Improving the nuclear energy sustainability by decreasing its environmental footprint. Guidelines from life cycle assessment simulations." Progress in Nuclear Energy 92, no. : 234-241.
Christophe Poinssot; Stéphane Bourg; Stéphane Grandjean; Bernard Boullis. The Sustainability, a Relevant Approach for Defining the Roadmap for Future Nuclear Fuel Cycles. Procedia Chemistry 2016, 21, 536 -544.
AMA StyleChristophe Poinssot, Stéphane Bourg, Stéphane Grandjean, Bernard Boullis. The Sustainability, a Relevant Approach for Defining the Roadmap for Future Nuclear Fuel Cycles. Procedia Chemistry. 2016; 21 ():536-544.
Chicago/Turabian StyleChristophe Poinssot; Stéphane Bourg; Stéphane Grandjean; Bernard Boullis. 2016. "The Sustainability, a Relevant Approach for Defining the Roadmap for Future Nuclear Fuel Cycles." Procedia Chemistry 21, no. : 536-544.
The EURATOM FP7 project SACSESS (Safety of Actinide Separation Processes) is in continuity of a long line of preceding EURATOM projects. SACSESS is organised along four domains, one of them related to the development of hydrometallurgical (i.e. solvent extraction based) actinide separations processes. Within this domain, the most promising processes developed in previous projects are further developed, improving their technology readiness level (TRL) towards the point at which safe industrial implementation will be achievable
Andreas Geist; Robin Taylor; Christian Ekberg; Philippe Guilbaud; Giuseppe Modolo; Stéphane Bourg. The SACSESS Hydrometallurgy Domain — An Overview. Procedia Chemistry 2016, 21, 218 -222.
AMA StyleAndreas Geist, Robin Taylor, Christian Ekberg, Philippe Guilbaud, Giuseppe Modolo, Stéphane Bourg. The SACSESS Hydrometallurgy Domain — An Overview. Procedia Chemistry. 2016; 21 ():218-222.
Chicago/Turabian StyleAndreas Geist; Robin Taylor; Christian Ekberg; Philippe Guilbaud; Giuseppe Modolo; Stéphane Bourg. 2016. "The SACSESS Hydrometallurgy Domain — An Overview." Procedia Chemistry 21, no. : 218-222.
Recycling of actinides by their separation from spent nuclear fuel, followed by transmutation in fast neutron reactors of Generation IV, is considered the most promising strategy for nuclear waste management. Closing the fuel cycle and burning long-lived actinides allows optimizing the use of natural resources and minimizing the long-term hazard of high-level nuclear waste. Moreover, improving the safety and sustainability of nuclear power worldwide. This paper presents the activities striving to meet these challenges, carried out under the Euratom FP7 collaborative project SACSESS (Safety of Actinide Separation Processes). Emphasis is put on the safety issues of fuel reprocessing and waste storage. Two types of actinide separation processes, hydrometallurgical and pyrometallurgical, are considered, as well as related aspects of material studies, process modeling and the radiolytic stability of solvent extraction systems. Education and training of young researchers in nuclear chemistry is of particular importance for further development of this field.
Stéphane Bourg; Andreas Geist; Jerzy Narbutt. SACSESS – the EURATOM FP7 project on actinide separation from spent nuclear fuels. Nukleonika 2015, 60, 809 -814.
AMA StyleStéphane Bourg, Andreas Geist, Jerzy Narbutt. SACSESS – the EURATOM FP7 project on actinide separation from spent nuclear fuels. Nukleonika. 2015; 60 (4):809-814.
Chicago/Turabian StyleStéphane Bourg; Andreas Geist; Jerzy Narbutt. 2015. "SACSESS – the EURATOM FP7 project on actinide separation from spent nuclear fuels." Nukleonika 60, no. 4: 809-814.
Energy perspectives for the current century are dominated by the anticipated significant increase of energy needs. Particularly, electricity consumption is anticipated to increase by a factor higher than two before 2050. Energy choices are considered as structuring political choices that implies a long-standing and stable policy based on objective criteria. LCA (life cycle analysis) is a structured basis for deriving relevant indicators which can allow the comparison of a wide range of impacts of different energy sources. Among the energy-mix, nuclear power is anticipated to have very low GHG-emissions. However, its viability is severely addressed by the public opinion after the Fukushima accident. Therefore, a global LCA of the French nuclear fuel cycle was performed as a reference model. Results were compared in terms of impact with other energy sources. It emphasized that the French nuclear energy is one of the less impacting energy, comparable with renewable energy. In a second, part, the French scenario was compared with an equivalent open fuel cycle scenario. It demonstrates that an open fuel cycle would require about 16% more natural uranium, would have a bigger environmental footprint on the “non radioactive indicators” and would produce a higher volume of high level radioactive waste
Ch. Poinssot; Stéphane Bourg; N. Ouvrier; N. Combernoux; Christine Rostaing; M. Vargas-Gonzalez; J. Bruno. Assessment of the environmental footprint of nuclear energy systems. Comparison between closed and open fuel cycles. Energy 2014, 69, 199 -211.
AMA StyleCh. Poinssot, Stéphane Bourg, N. Ouvrier, N. Combernoux, Christine Rostaing, M. Vargas-Gonzalez, J. Bruno. Assessment of the environmental footprint of nuclear energy systems. Comparison between closed and open fuel cycles. Energy. 2014; 69 ():199-211.
Chicago/Turabian StyleCh. Poinssot; Stéphane Bourg; N. Ouvrier; N. Combernoux; Christine Rostaing; M. Vargas-Gonzalez; J. Bruno. 2014. "Assessment of the environmental footprint of nuclear energy systems. Comparison between closed and open fuel cycles." Energy 69, no. : 199-211.
Stéphane Bourg; Christophe Poinssot; Andres Geist; Laurent Cassayre; Chris Rhodes; Christian Ekberg. Advanced Reprocessing Developments in Europe Status on European Projects ACSEPT and ACTINET-I3. Procedia Chemistry 2012, 7, 166 -171.
AMA StyleStéphane Bourg, Christophe Poinssot, Andres Geist, Laurent Cassayre, Chris Rhodes, Christian Ekberg. Advanced Reprocessing Developments in Europe Status on European Projects ACSEPT and ACTINET-I3. Procedia Chemistry. 2012; 7 ():166-171.
Chicago/Turabian StyleStéphane Bourg; Christophe Poinssot; Andres Geist; Laurent Cassayre; Chris Rhodes; Christian Ekberg. 2012. "Advanced Reprocessing Developments in Europe Status on European Projects ACSEPT and ACTINET-I3." Procedia Chemistry 7, no. : 166-171.
Actinide recycling by separation and transmutation is considered worldwide and particularly in several European countries as one of the most promising strategies to reduce the inventory of radioactive waste and to optimise the use of natural resources. With its multidisciplinary consortium of 34 partners from 12 European countries plus Australia and Japan, the European Research Project ACSEPT (Actinide reCycling by SEParation and Transmutation) aims at contributing to the development of this strategy by studying both hydrometallurgical and pyrochemical partitioning routes. ACSEPT is organised into three technical domains: After more than two years of work, significant progress was achieved in process development with the demonstration of the SANEX and innovative SANEX flowsheets. Chemical systems were selected for GANEX and are under study. In addition, efforts were made to increase collaborations, mutualise and homogenise procedures and share good practices. Based on these assessments, it is now time to look at the future challenges to overcome. A training and education program is implemented to share the knowledge among the partitioning community, present and future generations of researchers. Specific attention is paid to the funding of post-doctorate fellowships, two having been appointed respectively at the end of 2008 and at the end of 2009. Through this training and education programme, the first ACSEPT International Workshop was organised last March in Lisbon, Portugal. It gave an emphasis to young researchers’ contributions (two thirds of the contributions) and allowed young scientists to meet and exchange with international recognised experts.
Stéphane Bourg; C. Hill; C. Caravaca; C. Rhodes; C. Ekberg; R. Taylor; Andreas Geist; Giuseppe Modolo; L. Cassayre; R. Malmbeck; M. Harrison; G. De Angelis; A. Espartero; Sylvie Bouvet; N. Ouvrier. ACSEPT—Partitioning technologies and actinide science: Towards pilot facilities in Europe. Nuclear Engineering and Design 2011, 241, 3427 -3435.
AMA StyleStéphane Bourg, C. Hill, C. Caravaca, C. Rhodes, C. Ekberg, R. Taylor, Andreas Geist, Giuseppe Modolo, L. Cassayre, R. Malmbeck, M. Harrison, G. De Angelis, A. Espartero, Sylvie Bouvet, N. Ouvrier. ACSEPT—Partitioning technologies and actinide science: Towards pilot facilities in Europe. Nuclear Engineering and Design. 2011; 241 (9):3427-3435.
Chicago/Turabian StyleStéphane Bourg; C. Hill; C. Caravaca; C. Rhodes; C. Ekberg; R. Taylor; Andreas Geist; Giuseppe Modolo; L. Cassayre; R. Malmbeck; M. Harrison; G. De Angelis; A. Espartero; Sylvie Bouvet; N. Ouvrier. 2011. "ACSEPT—Partitioning technologies and actinide science: Towards pilot facilities in Europe." Nuclear Engineering and Design 241, no. 9: 3427-3435.
Stéphane Bourg; Andres Geist; Concha Caravaca; Chris Rhodes; Christian Ekberg. ACSEPT – Status in Advanced Separation Process Developments in Europe. Revue Générale Nucléaire 2011, 82 -86.
AMA StyleStéphane Bourg, Andres Geist, Concha Caravaca, Chris Rhodes, Christian Ekberg. ACSEPT – Status in Advanced Separation Process Developments in Europe. Revue Générale Nucléaire. 2011; (5):82-86.
Chicago/Turabian StyleStéphane Bourg; Andres Geist; Concha Caravaca; Chris Rhodes; Christian Ekberg. 2011. "ACSEPT – Status in Advanced Separation Process Developments in Europe." Revue Générale Nucléaire , no. 5: 82-86.
Ces études se placent dans le contexte du développement de solutions innovantes pour l'extraction d'éléments transuraniens de solutions d'acide nitrique fortement radioactive. Ainsi, des matériaux avancés, de type silices hybrides, obtenus par hydrolyse puis condensation d'espèces moléculaires contenant des fonctions complexantes, ont été développés afin d'améliorer les techniques d'extraction par voie solide–liquide. L'influence de la nature du groupe extractant, de la microstructure et de la concentration en fonction complexante dans le solide sur le coefficient de partage solide–liquide a été déterminée dans le cas de l'extraction de l'américium et du plutonium d'une solution d'acide nitrique. Des essais préliminaires portant sur la séparation américium–europium par ces matériaux a également ont été abordés.
Daniel J.M. Meyer; Stéphane Bourg; Olivier Conocar; Jean-Charles Broudic; Joël J.E. Moreau; Michel Wong Chi Man. Extraction of plutonium and americium using silica hybrid materials. Comptes Rendus. Chimie 2007, 10, 1001 -1009.
AMA StyleDaniel J.M. Meyer, Stéphane Bourg, Olivier Conocar, Jean-Charles Broudic, Joël J.E. Moreau, Michel Wong Chi Man. Extraction of plutonium and americium using silica hybrid materials. Comptes Rendus. Chimie. 2007; 10 (10-11):1001-1009.
Chicago/Turabian StyleDaniel J.M. Meyer; Stéphane Bourg; Olivier Conocar; Jean-Charles Broudic; Joël J.E. Moreau; Michel Wong Chi Man. 2007. "Extraction of plutonium and americium using silica hybrid materials." Comptes Rendus. Chimie 10, no. 10-11: 1001-1009.
The structure of the fuels for the future Gen IV nuclear reactors will be totally different from those of PWR, especially for the GFR concept including a closed cycle. In these reactors, fissile materials (carbides or nitrides of actinides) should be surrounded by an inert matrix. In order to build a reprocessing process scheme, the behavior of the potential inert matrices (silicon carbide, titanium nitride, and zirconium carbide and nitride) was studied by hydro- and pyrometallurgy. This paper deals with the chlorination results at high temperature by pyrometallurgy. For the first time, the reactivity of the matrix towards chlorine gas was assessed in the gas phase. TiN, ZrN and ZrC are very reactive from 400 °C whereas it is necessary to be over 900 °C for SiC to be as fast. In molten chloride melts, the bubbling of chlorine gas is less efficient than in gas phase but it is possible to attack the matrices. Electrochemical methods were also used to dissolve the refractory materials, leading to promising results with TiN, ZrN and ZrC. The massive SiC samples used were not conductive enough to be studied and in this case specific SiC-coated carbon electrodes were used. The key point of these studies was to find a method to separate the matrix compounds from the fissile material in order to link the head to the core of the process (electrochemical separation or liquid–liquid reductive extraction in the case of a pyrochemical reprocessing). IDT A0200 C0400
Stéphane Bourg; F. Peron; J. Lacquement. The evaluation of the pyrochemistry for the treatment of Gen IV nuclear fuels – Inert matrix chlorination studies in the gas phase or molten chloride salts. Journal of Nuclear Materials 2007, 360, 58 -63.
AMA StyleStéphane Bourg, F. Peron, J. Lacquement. The evaluation of the pyrochemistry for the treatment of Gen IV nuclear fuels – Inert matrix chlorination studies in the gas phase or molten chloride salts. Journal of Nuclear Materials. 2007; 360 (1):58-63.
Chicago/Turabian StyleStéphane Bourg; F. Peron; J. Lacquement. 2007. "The evaluation of the pyrochemistry for the treatment of Gen IV nuclear fuels – Inert matrix chlorination studies in the gas phase or molten chloride salts." Journal of Nuclear Materials 360, no. 1: 58-63.
Considering the criteria put forward by the Generation IV Forum to select future nuclear systems (preservation of resources, minimization of final waste impact, economics, etc.), the impetus for the very high-temperature He-cooled reactor raises the issue of processing the fuel in the context of a closed cycle with actinide recycling. Due to the unique structure of the particle fuel used for this class of reactors, the difficulties essentially involve accessibility to the uranium kernels coated by carbon and SiC layers and dispersed in a large volume of graphite. Starting from past experience in this field, a research program has been recently undertaken by the CEA to propose attractive solutions. The mechanical extraction of compacts from the spent fuel blocks appears to be a promising approach, as well as removing the graphite from the compacts by pulsed currents to free the particles. Subsequent removal of the carbon and silicon carbide layers by high temperature oxidation or by carbochlorination to access the kernels is assessed. For actinide recycling, gelation appears to be a suitable process for fabricating the kernels. This paper provides a brief overviews of the developments currently in progress at the CEA.
Michel Masson; Stéphane Grandjean; Jérôme Lacquement; Stéphane Bourg; Jean Marie Delauzun; Jacques Lacombe. Block-type HTGR spent fuel processing: CEA investigation program and initial results. Nuclear Engineering and Design 2006, 236, 516 -525.
AMA StyleMichel Masson, Stéphane Grandjean, Jérôme Lacquement, Stéphane Bourg, Jean Marie Delauzun, Jacques Lacombe. Block-type HTGR spent fuel processing: CEA investigation program and initial results. Nuclear Engineering and Design. 2006; 236 (5-6):516-525.
Chicago/Turabian StyleMichel Masson; Stéphane Grandjean; Jérôme Lacquement; Stéphane Bourg; Jean Marie Delauzun; Jacques Lacombe. 2006. "Block-type HTGR spent fuel processing: CEA investigation program and initial results." Nuclear Engineering and Design 236, no. 5-6: 516-525.
Hybrid materials with complexing properties toward lanthanides(III), americium(III), and plutonium(IV) are described. These new silica-based materials, containing malonamide ligands, have been prepared by sol−gel hydrolysis and condensation of a silylated tetraethylmalonamide in the presence of tetraethoxysilane (TEOS). A family of these hybrid materials was obtained by varying the amount of TEOS, the catalyst, and the Rw ratio (amount of water added per Si−O bonds). The porous hybrids exhibited BET surface areas up to 300 m2 g-1 with the average pore diameter ranging from 30 to 90 Å. The new hybrids were used as solid phase extractants in batch experiments for the extraction of americium and plutonium from high-level liquid wastes. The hybrids were shown to be highly efficient materials in solid−liquid extraction, exhibiting distribution coefficients up to 104 and loading capacities up to 0.46 mequiv/g. They compared favorably to related silica-based material containing malonamide immobilized by classical techniques. The sol−gel approach allows one to adjust the ligand loading and to achieve some control and some tuning of the ligand environment since the oxide matrix is built around the complexing moieties. The use of templating techniques was also studied to enhance the extracting properties.
Stéphane Bourg; † Jean-Charles Broudic; Olivier Conocar; Joël J. E. Moreau; † And Daniel Meyer; Michel Wong Chi Man‡. Tailoring of Organically Modified Silicas for the Solid−Liquid Extraction of Actinides. Chemistry of Materials 2001, 13, 491 -499.
AMA StyleStéphane Bourg, † Jean-Charles Broudic, Olivier Conocar, Joël J. E. Moreau, † And Daniel Meyer, Michel Wong Chi Man‡. Tailoring of Organically Modified Silicas for the Solid−Liquid Extraction of Actinides. Chemistry of Materials. 2001; 13 (2):491-499.
Chicago/Turabian StyleStéphane Bourg; † Jean-Charles Broudic; Olivier Conocar; Joël J. E. Moreau; † And Daniel Meyer; Michel Wong Chi Man‡. 2001. "Tailoring of Organically Modified Silicas for the Solid−Liquid Extraction of Actinides." Chemistry of Materials 13, no. 2: 491-499.
Reactions of 2,5-disilahexane with cobalt or iron carbonyl were performed in order to prepare cobalt or iron organosilicon ceramic precursors. Characterization of their structure by NMR and IR spectroscopies indicates the presence of mixed oligomeric and molecular species. Pyrolysis under argon at 1000 °C gives multiphase ceramics in high yields. Part of the CO ligands were incorporated during the thermal decomposition. Materials were characterized by X-ray, Raman, TEM and magnetic susceptibility analyses. For cobalt and iron, formation of metal-rich nodules included in a homogeneous matrix is observed for the sample pyrolyzed at 1000 °C. Crystalline Fe3Si or Co2Si are detected and the presence of amorphous oxide or oxycarbide phases is consistent with the high oxygen level. Between 1200 °C and 1400 °C, a carbothermal reduction process occurs at different temperatures for the iron and the cobalt precursors. Elimination of CO and SiO occurs with modification of the ceramic phases. Formation of SiC and silicides (FeSi for I and CoSi for II) is observed. Melting of the Fe3Si phase leads to the formation of spherical metallic particles.
Stéphane Bourg; Bruno Boury; Robert J. P. Corriu. Mixed Si/C/M/O ceramics from 2,5-disilahexane/metal carbonyl (MFe and Co). Journal of Materials Chemistry 1998, 8, 1001 -1006.
AMA StyleStéphane Bourg, Bruno Boury, Robert J. P. Corriu. Mixed Si/C/M/O ceramics from 2,5-disilahexane/metal carbonyl (MFe and Co). Journal of Materials Chemistry. 1998; 8 (4):1001-1006.
Chicago/Turabian StyleStéphane Bourg; Bruno Boury; Robert J. P. Corriu. 1998. "Mixed Si/C/M/O ceramics from 2,5-disilahexane/metal carbonyl (MFe and Co)." Journal of Materials Chemistry 8, no. 4: 1001-1006.