SOLUBILITY OF PLUTONIUM TRIFLUORIDE IN FUSED-ALKALI FLUORIDE—BERYLLIUM FLUORIDE MIXTURES1

The solubility of PuF/sub 3/ in five LiF-BeF/sub 2/ mixtures, three determined at 550 to 650 deg C. The data follow a linear relationship when plotted as log of molar concentration of PuF/sub 3/ versus l/T( deg K.). The solubility of PuF/sub 3/ in these solvents is rather low, varying from about 0.4 to 2.5 mole% at 650 deg C, and from 0.16 to 1.0 mole% at 550 deg C. Minima in solubility-composition diagrams for the binary systems at 565 deg occur at 63 mole% LiF (0.3 mole% PuF/sub 3/) and 57 mole% NaF (0.18 mole % PuF/sub 3/). The effect of ThF/sub 4/, BaF/sub 2/, and CeF/sub 3/ in diminishing the solubility of PuF/sub 3/ in of PuF/sub 3/ in the mixture LiF-BeF/sub 2/-UF/sub 4/ (70-10-20 mole %) was found to be higher than in an LiF-BeF/sub 2/ solvent having the same concentration of LiF. (auth)