JAEA thermodynamic database for performance assessment of geological disposal of high-level and TRU wastes; Refinement of thermodynamic data for trivalent actinoids and samarium

Kitamura, Akira  ; Fujiwara, Kenso ; Yui, Mikazu

Within the scope of the JAEA thermodynamic database project for performance assessment of geological disposal of high-level radioactive and TRU wastes, refinement of the thermodynamic data for the inorganic compounds and complexes of actinium, plutonium(III), americium, curium and samarium was carried out. Refinement of thermodynamic data of these elements was performed on a basis of the thermodynamic database for americium published by the Nuclear Energy Agency in the Organisation for Economic Co-operation and Development (OECD/NEA). Based on the similarity of chemical properties among trivalent actinides and samarium, complementary thermodynamic data for their species expected under the geological disposal condition were selected to complete the thermodynamic data set for the performance assessment of geological disposal of radioactive wastes.