Fission Product Release from UO2 in Air During 58 Temperature Ramps

Abstract

Results are reported from an ongoing series of experiments investigating the oxidative release of fission products from fragments of irradiated U02. The experiments detailed in this paper cover transient temperature tests below 1100 degrees C including heating or cooling in air at various rates. The oxidation behaviour of unirradiated U02 in similar conditions was also investigated and is reported here. Fission product releases of Xe, Ru and I were found to depend on the origin of fragments from an irradiated element in terms of fuel pellet radius. Central fuel chips produced faster releases, at lower temperatures, of I, Ru and Xe than did U02 taken from the fuel pellet periphery.