Development of high-level liquid waste conditioning technology for advanced nuclear fuel cycle, 21; Overall results and evaluation

Morita, Yasuji  ; Yamagishi, Isao ; Sato, Soichi ; Kirishima, Akira*; Fujii, Toshiyuki*; Uehara, Akihiro*; Tsukada, Takeshi*; Usami, Tsuyoshi*; Kurosaki, Ken*

Development of high-level liquid waste (HLW) conditioning technology for advanced nuclear fuel cycle was conducted for the purpose of the reduction of potential problems in the verification process for HLW. It includes development of separation technology for Mo, Pd and Ru from HLW and development of separate treatment of the insoluble residue. The present report gives the overall results of the research and development and their evaluation. For the Mo separation, the extraction process with HDEHP was developed by performing continuous extraction tests and process simulation by a calculation code. An extraction process for Pd by 5,8-diethyl-7-hydroxy-6-dodecanone oxime was also developed, but was evaluated as less mature than the HEDHP process. As Ru separation method, volatilization of RuO after electrochemical oxidation was examined. Dissolution residue (metal alloy) and recovered Pd and Ru were solidified together by hot-press method.