Thermochemical Aspects of High Plutonia (44%Pu) MOX Fuel

Use of high plutonia MOX as fuel is contemplated from the point of view of rapid disposition of plutonium and from economic power generation. As part of the fuel development programme, high plutonia MOX (44%) is undergoing test irradiation at FBTR, Kalpakkam. Several thermophysical and thermochemical properties need to be evaluated for this composition. This includes phase stability, melting temperature, vapour chemistry, oxygen potential, component redistribution under steep thermal gradient and compatibility studies between fuel-clad and fuel-coolant. Some of the thermochemical aspects are summarized in this paper.