Recent progress of JAEA-CRIEPI joint study for metal pyroreprocessing at CPF

Kitawaki, Shinichi ; Nakayoshi, Akira  ; Fukushima, Mineo ; Koizumi, Tsutomu; Kurata, Masaki* ; Yahagi, Noboru*

JAEA is developing the pyroreprocessing by collaboration with CRIEPI. The test using U began in 2002, and the test using PuO and unirradiated MOX were ended in 2008. The reduction of UO pellets by using Li-reduction method, the electrowinning using reduced pellets, the separation of adhered salt with deposit by distillation, and the ingot formation of deposit were performed. As a result, 99% of the loaded U is recovered as metal ingot. The tests similar to U tests were performed by using PuO. As a result, Pu was successfully recovered with U metal. In the MOX test, the mass balance of Pu was maintained at 100% with respect to the initial amount. We try to form the U-Pu-Zr alloy by using reduced MOX. After 2009, the process development that uses the alloy will be continued.