Development of high-level liquid waste conditioning technology for advanced nuclear fuel cycle, 19; Dependence of dissolution rate of insoluble residue on its composition

Usami, Tsuyoshi*; Tsukada, Takeshi*; Yamagishi, Isao ; Morita, Yasuji  

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. To evaluate characteristics of the insoluble residue, simulated residue of metal alloy composed of Ru, Mo, Rh and Pd was dissolved with heated nitric acid. The results showed that higher concentration of Pd in the alloy makes the alloy easier to be dissolved, and higher concentration of Ru makes the alloy more difficult to be dissolved.