[en] The thermodynamic feasibility of decontaminating a (Th,U)O₂ fuel by volatilization during conversion to the carbide and by subsequent electron beam melting was examined. Experiments on simulated fuels containing selected fission product element additions were perfomed and the results were generally in agreement with predicted behavior. The alkaline earth and rare earth elements were rather effectively removed, particularly from the substoichiometric monocarbide whereas zirconium, molybdenum and ruthenium were little affected