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

A process is described for synthesizing a mixed peroxide or hydroxo-peroxide of an actinyl and at least one cation X1, wherein the actinyl is a uranyl or neptunyl and the at least one cation X1 is a di-, tri- or tetra-charged metal cation. This process includes the reaction in a solvent of a salt of the at least one cation X1 with a compound C2 selected from mixed peroxides and hydroxo-peroxides of the actinyl and of at least one singly charged cation X2, whereby compound C2 is converted to the peroxide or hydroxo-peroxide by replacement of the at least one cation X2 by said at least one cation X1. Also disclosed is a process for synthesizing a mixed oxide of an actinide selected from uranium and neptunium, and of at least one metal able to form a di-, tri- or tetra-charged cation, which implements the preceding synthesis process. The disclosure further relates to a mixed peroxide or hydroxo-peroxide of an actinyl and of at least one di-, tri- or tetra-charged metal cation, and the use thereof for the preparation of a mixed oxide of an actinide and of at least this metal.