JAEA thermodynamic database for performance assessment of geological disposal of high-level and TRU wastes; Selection of thermodynamic data on cobalt and nickel

Kitamura, Akira  ; Kirishima, Akira*; Saito, Takumi*; Shibutani, Sanae*; Tochiyama, Osamu*; Yui, Mikazu

Within the scope of the JAEA thermodynamic database project for performance assessment of geological disposal of high-level and TRU radioactive wastes, the selection of the thermodynamic data on the inorganic compounds and complexes of cobalt and nickel have been carried out. For cobalt, extensive literature survey has been performed and all the obtained literatures have been carefully reviewed to select the thermodynamic data. Selection of thermodynamic data of nickel has been based on a thermodynamic database published by the OECD/NEA, which has been carefully reviewed by the authors, and then thermodynamic data have been selected after surveying latest literatures. Based on the similarity of chemical properties between cobalt and nickel, complementary thermodynamic data of nickel and cobalt species expected under the geological disposal condition have been selected to complete the thermodynamic data set for the performance assessment of geological disposal of radioactive wastes.