Book	FZJ-2016-04028

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Institute of Energy and Climate Research IEK-6: Nuclear Waste Management Report 2013 / 2014 Material Science for Nuclear Waste Management

Neumeier, S. (Editor)FZJ* ; Klinkenberg, M. (Editor)FZJ* ; Bosbach, D. (Editor)FZJ*

2016
Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag Jülich
ISBN: 978-3-95806-155-2

Please use a persistent id in citations: http://hdl.handle.net/2128/11969

Abstract: This is the third bi-annual report of the $\textbf{Nuclear Waste Management section of the Institute of Energy and Climate Research (IEK-6) at Forschungszentrum Jülich}$ since 2009 – almost a tradition. Our institute has seen two more years with exciting scientific work, but also major changes regarding nuclear energy in Germany and beyond. After the reactor accident in Fukushima (Japan) in 2011, it was decided in Germany to phase out electricity production by nuclear energy by 2022. It seems clear, that the decommissioning of the nuclear power plants will take several decades. The German nuclear waste repository Konrad for radioactive waste with negligible heat generation (all low level and some of the intermediate level radioactive waste) will start operation in the next decade. The new site selection act from 2013 re-defines the selection procedure for the German high level nuclear waste repository. Independently of the decision to stop electricity production by nuclear energy, Germany has to manage and ultimately dispose of its nuclear waste in a safe way. Our basic and applied research for the safe management of nuclear waste is focused on radiochemistry and materials chemistry aspects – it is focused on the behaviour of radionuclides and radioactive waste materials within the back-end of the nuclear fuel cycle. It is organized in four areas: (1) research supporting the scientific basis of the safety case of a deep geological repository for high level nuclear waste, (2) fundamental structure research of radionuclide containing (waste) materials (3) R & D for waste management concepts for special nuclear wastes and (4) international safeguards. A number of excellent scientific results have been published in more than 80 papers in international peer-reviewed scientific journals in 2013 - 2014. Here, I would like to mention four selected scientific highlights – more can be found in this report:(1) The retention of radionuclides within a nuclear waste repository system by secondary phases for the long-term safety assessment is one of the major research topics in the institute. The fundamental understanding of a long-standing open issue regarding the thermodynamics of radium-barium-sulfate $\textbf{solid solutions}$ and its applicability in long-term safety assessments for nuclear waste disposal could be resolved. This was achieved by a novel approach combining atomistic simulations, radiochemical batch-type laboratory experiments and modern analytical techniques supported by thermodynamic modelling allowing a reliable description of Ra solubility control by a (Ba,Ra)SO$_{4}$ solid solution. This research is supported by the Swedish waste management agency SKB.(2) A major step forward was achieved regarding the prediction of actinide- and lanthanide bearing materials properties by $\textbf{atomistic simulations}$. Performance tests of the DFT+U method for calculations of f-element-bearing systems (the Hubbard U parameter derived from first principle methods) showed that this method, in contrast to standard DFT, results inexceptionally good predictions of the formation and reaction enthalpies as well as the structures of lanthanide- and actinide-bearing materials.(3) The $\textbf{actinide solid state chemistry}$ group has been very active in recent years tounravel the crystal structure of actinide containing oxo-salts. From the 1101 new crystal structure entries in the ICSD crystal structure database between 2005 and 2012, Prof. Evgeny Alekseev has contributed to 98 entries (almost 10%). [...]

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Contributing Institute(s):

1. Nukleare Entsorgung und Reaktorsicherheit (IEK-6)

Research Program(s):

1. 161 - Nuclear Waste Management (POF3-161) (POF3-161)

Appears in the scientific report 2016

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Database coverage:
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