Synthesis of Actinide Nitrides in Molten Cadmium

Pyrochemical processing has several advantages over conventional wet processing for the treatment of spent nitride fuel. Besides the molten salt electrorefining of nitride fuel, actinide nitride formation in and recovery from the liquid cadmium cathode is a key technology in the nitride fuel cycle with pyrochemical processing. It was found that heating a cadmium alloy containing plutonium and uranium at 973 K under a nitrogen gas stream resulted in the simultaneous nitridation of the actinides and the distillation of cadmium. Furthermore, nitride pellets were prepared from the powder recovered without any milling or granulating process. The results obtained in the present study suggested that the nitride fuel cycle with pyrochemical processing is technologically feasible for transmutation of minor actinides and advanced fast reactors.