Contribution to the knowledge of the electrochemical properties of actinides in non-aqueous media II: The reduction of hexavalent uranium in various organic solvents

Abstract

The electrochemical behaviour of hexavalent uranium is reported in various organic solvents at room temperature and also in hexamethylphosphoramide, dimethylsulphone, sulpholane between 310 and 400 K. The reduction of UO 2 2+ proceeds in two steps, leading to tetravalent uranium. Depending on the solvent acidity, the tetravalent species is either soluble or precipitates as UO 2(cr). Numerous additional kinetic phenomena are evidenced in all the reactions. Special attention is paid to the deposition of UO 2(cr) in macroscopic quantities.