PROCESS FOR REPROCESSING A SPENT NUCLEAR FUEL AND OF PREPARING A MIXED URANIUM-PLUTONIUM OXIDE

摘要

Recycling process of an used nuclear fuel and preparation of a mixed oxide of uranium and plutonium comprises: separation of uranium and plutonium from fission products present in an aqueous nitric solution resulting from the used nuclear fuel dissolved in nitric acid, distribution of obtained uranium and plutonium in two aqueous phases, where one of the aqueous phase contains plutonium and uranium, and the other aqueous phase has only uranium; purification of obtained plutonium and uranium; and co-conversion of obtained plutonium and uranium into a mixed oxide of uranium and plutonium. Recycling process of an used nuclear fuel and preparation of a mixed oxide of uranium and plutonium comprises: separation of uranium-(VI) and plutonium-(IV) (where VI and IV are the oxidation number) from fission products, americium and curium present in an aqueous nitric solution resulting from the used nuclear fuel dissolved in nitric acid, where the separation comprises co-extraction of the aqueous solution containing uranium and plutonium by contacting the solution with a solvent phase (i.e. immiscible with water) containing an extracting agent in the presence of an organic diluent; distribution of obtained uranium and plutonium in two aqueous phases, where the first aqueous containing plutonium and uranium, and the second aqueous phase containing uranium with out plutonium; purification of plutonium and uranium from the first aqueous phase; and co-conversion of obtained plutonium and uranium into a mixed oxide of uranium and plutonium.