CRTA Study of the Reduction of UO2F2 into UO2 by Dry H2

The reduction of UO2F2 by dry H2 was studied by Controlled Rate EGA, with a special set-up operating under a gas flow under atmospheric pressure. At the constant transformation rate selected, this reduction apparently takes place in one main step, around 450°C (for a total duration of 100 h), followed by a small exothermic step. The final product is a stoichiometric, well crystallized UO2. XRD analysis shows the occurrence of two successive intermediates of which one has a structure close to that of UO2, but with interstitial fluorine atoms.