Identification of fission products released from irradiated uranium/aluminum alloy fuel

Out-of-pile studies of fission product release from melted reactor fuels have been carried out by inductively heating the fuel, entraining the released fission products in a flowing gas and separating the fission products in a thermal gradient tube and filters. Identification of the chemical form of each fission product is implied from its location in the apparatus and from chemical analysis of the apparatus surfaces after melting is accomplished. Determination of the chemical forms of fission products in this manner, however, does not identify the nature of the fission product within the fuel matrix or on the fuel surface. The possibility that fission products undergo vapor phase or surface reactions during the time between their release and deposition on the surface of the apparatus masks the true identity of the chemical forms of fission products within the fuel matrix or on the surface of the molten fuel