APPARATUS FOR THE GASOMETRIC STUDY OF SOLID-GAS REACTIONS: SODIUM FLUORIDE WITH HYDROGEN FLUORIDE AND URANIUM HEXAFLUORIDE

A gasometric apparatus for rapidly characterizing dissociation pressures, sorption equilibrium and kinetics, chemical states, and decomposition conditions was built and tested. The method involves the measurement of quantities of gases reacting with or evolving from known quantities of solid. Accuracies of better than plus or minus 1% were attained. In testing the capabilities of tue apparatus, the dissociation pressures of hydrogen fluoride and uranium hexafluoride over their respective complexes with sodium fluoride, and the decomposition of the uranium hexafluoride complex to give elemental fluorine were verified. Additionally, a test for sorption of uranium hexafluoride on sodium fluoride was developed, the existence of the compound Na/ sub 2/UF/sub 8/ was demonstrated, a more active form of sodium fluoride was made, the stability of the pentavalent uranium-- sodium fluoride complex was studied, data leading to a postulated new compound (NaF)/sub 2/(UF/sub 6/)(HF) was obtained, and the interaction of hydrogen fluoride and uranium hexafluoride on sodium fluoride was studied. (auth)