Processing of uranium oxide powders in a fluidized-bed reactor. I. Experimental

The oxidation of UN powders was carried out in a spout-type fluidized-bed reactor in gas mixtures of oxygen and argon, and over the temperature range of 200–500 °C. The rate of the conversion from UN to U3O8 powders was measured using gas chromatography and found to be dependent on temperature, partial pressure of oxygen and gas flowrate. The solid reactants and products were analyzed using SEM and XRD. Based on the experimental results, the conversion process was explained by the crackling core model.