PROCESS FOR THE SYNTHESIS OF A MIXED PEROXIDE OR HYDROXOPEROXIDE OF AN ACTINYL AND AT LEAST ONE DI-, TRI- OR TETRACHARGE METAL CATION, PEROXIDE OR MIXED HYDROXOPEROXIDE THUS OBTAINED AND THEIR APPLICATIONS

摘要

The invention relates to a process for the synthesis of a mixed peroxide or hydroxoperoxide of an actinyl and of at least one cation X1, in which the actinyl is a uranyl or a neptunyl and the said at least one cation X1 is a di-, tri- or tetrachlorated cation of a metal. This process comprises the reaction, in a solvent, of a salt of said at least one cation X1 with a compound C2 chosen from mixed peroxides and hydroxoperoxides of actinyl and of at least one cation X2 which is monocharged, whereby the compound C2 is converted to peroxide or hydroxo peroxide by replacing said at least one cation X2 with said at least one cation X1. It also relates to a process for synthesizing a mixed oxide of an actinide chosen from uranium and neptunium, and of at least one metal capable of forming a di-, tri- or tetracharged cation, which the preceding synthesis method. It also relates to a mixed peroxide or hydroxoperoxide of an actinyl and of at least one di-, tri- or tetracharged cation of a metal, as well as to its use for the preparation of a mixed oxide of a actinide and at least that metal. Applications: manufacture of mixed actinide oxides suitable for use in the manufacture of nuclear fuel pellets or transmutation targets, decontamination of contaminated effluents with radionuclides from nuclear installations, etc.