LABORATORY INVESTIGATIONS IN SUPPORT OF FLUID-BED FLUORIDE VOLATILITY PROCESSES. PART V. THE RADIATION CHEMISTRY OF PLUTONIUM HEXAFLUORIDE

Abstract

Plutonium hexafluoride exposed to fission product gamma radiation decomposes to form plutonium tetrafluoride and elemental fluorine with a G value of 7.5 plus or minus 1.7. Addition of one atmosphere of helium to plutonium hexafluoride at a pressure of approximates 80 mm Hg does not significantly change the G value for the decomposition compared with that for pure plutonium hexafluoride. Addition of 2 atmos of helium to plutonium hexafluoride at approximates 80 mm Hg results in a G value for the decomposition of 5.8 plus or minus 0.9. A study of the effect of krypton on the decomposition of plutonium hexafluoride by gamma radiation revealed a marked enhancement of the decomposition at an electron fraction of No such enhancement was observed at an exposure dose of 2 x 10/sup 8/ rads. Addition of fluorine or oxygen to plutonium hexafluoride resulted in a G value for the decomposition that was less than that obtained from the irradiation of pure plutonium hexafluoride. Irradiation of mixtures of plutonium tetrafluoride and elemental fluorine produced plutonium hexafluoride in concentrations greater than that calculated from the thermodynamic equilibrium constant at the temperature of the irradiations. (auth)