U, Pu corbides IReprocessing of nuclear fuels /Photochemistry / Oxidation of organic Compounds/Th? extraction Summaty A photochemical oxidation process is discussed in the context of the reprocessing of mixed uranium, plutonium carbide fuels. The organic Compounds formed in the Solution of the dissolved carbides can be removed by photolysis in a head-end treatment prior to the PUREX extraction process.The course of the photochemical oxidation of the carbonaceous by-products as a function of nitric acid molarity is foUowed by measurements of the formation of CO,, by the changes in the absorption spectrum of the Solution and by the Variation in the extractability of plutonium with 30% TBP.Dissolution in a circulation set-up with the concomitant exposure to light is the most efficient.