抄録
A novel reprocessing system with recovery of actinides, long-lived fission products (LLFP) and valuable rare metal fission products (RMFP) has been proposed. This process is based on ion exchange (IX) and catalytic electrolytic extraction (CEE). The pre-filtration step using tertiary pyridine-type anion-exchange resin is set prior to the main actinide recovery steps in this system. The perfect isolation of platinum group elements (Pt-G) such as 106Ru from fuel dissolver solution was successfully demonstrated for irradiated mixed oxide (MOX) fuel. The CEE method, being set as a post-pre-filtration process, was applicable to separation of RMFP including TcO4- and ReO4- by selective and accelerative deposition with Pd2+ as a catalyst. Quaternary Pd-Ru-Rh-Re deposited Pt electrodes showed the highest cathodic current. The catalytic ability is about twice superior to that of the base Pt electrode when used for artificial sea water as well as alkaline solution. The recovery and separation of actinides and RMFP by a multi-functional reprocessing system consisting of IX and CEE will minimize the quantity and improve the quality of high level liquid waste (HLLW). The recovered RMFP will be used as a “FP-catalyst” for hydrogen production in water electrolysis.
