Thermodynamic study on solubility of actinide hydrous oxides and stability of the colloids

2015 Fiscal Year Final Research Report

• Project/Area Number: 24360393
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Nuclear engineering
• Research Institution: Kyoto University
• Principal Investigator: Sasaki Takayuki 京都大学, 工学(系)研究科(研究院), 教授 (60314291)
• Co-Investigator(Kenkyū-buntansha): MORIYAMA Hirotake 京都大学, 原子炉実験所, 教授 (90127150) ; KOBAYASHI Taishi 京都大学, 工学研究科, 助教 (80630269)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: 放射性廃棄物処分 / 4価アクチニド / コロイド / 錯生成 / 溶解度 / 熱力学モデル

Outline of Final Research Achievements

Understanding of thermodynamic stability of actinide ions and its compounds including colloids is indispensable for safety assessment for the disposal of high level radioactive waste. In this project, basic studies in actinide aqueous solution chemistry have been performed to obtain the knowledge of formation constants, solubility products, and the chemical conditions of soluble species and precipitation. Through the systematic experimental study of the binary (An-OH) and the ternary (An-OH-inorganic ions, -humic substances) systems at a given solution condition, the apparent solubility data and the long term stability of species and solid phases were analyzed by the proposed thermodynamic models. The results are expected to contribute a reliability improvement of radioactive waste management in Japan and other countries.

Free Research Field

放射性廃棄物処分、アクチニド化学、熱力学