The reaction between dissociated fluorine and oxides of uranium

Fluorine at 1–5 torr pressure was dissociated with a microwave discharge and passed over samples of UO₂ or U₃O₈. The only reaction products were UF₆ and O₂. The reaction rates were independent of particle size and sample depth, but depended upon the geometric surface of the sample. Kinetic studies were interpreted to show that F-atoms react immediately upon contact with the surface, and that both F₂-molecules and F-atoms react with the sample. When the ratio, F/F₂, is relatively low, the partial pressure of F-atoms is rate determining. When the ratio, F/F₂, is relatively high the rate of diffusion of total fluorine (F+F₂) to the surface is rate determining.