Carbothermic synthesis of high purity plutonium nitride from plutonium oxide

Synthetic conditions of PuN from carbothermic reduction of PuO2 has been studied in a mixed 8%H2 + 92%N2 stream at a temperature range of 1,270 -- 1,6800C. In the course of both reactions of the carbothermic synthesis of PuN from PuO2 and the hydrogenation of C, the vaporization loss of Pu was observed. It increased with temperature in the temperature range of 1,350 -- 1,4500C, and reached to a constant value 1.3% of total Pu in the temperature range of 1,450 -- 1,6800C, at which PuN was synthesized at a reaction rate of high enough. The minimum mixing ratio (C/PuO2, mole ratio) for the formation of high purity PuN depends on temperature. The value is 2.15 for 1,6200C and 2.35 for 1,6800C. The oxygen and carbon impurities in the PuN obtained were found to be 0.095 -- 0.028 and 0.17 -- 0.012 w/o, respectively. (author)