Electrochemical reduction of trivalent uranium ions in molten chlorides

The electrochemical behaviour of U-III in molten salts was studied at 715 circle C under argon atmosphere in a molten equimolar NaCl-KCl mixture containing uranium ions in oxidation state III (UCl3). Three different complementary electrochemical methods were used, namely cyclic voltammetry, chronopotentiometry and square wave voltammetry. These techniques provide data to explain the electroreduction mechanism. The reduction of UIII in the NaCl-KCl mixture occurs in a single step with an exchange of three electrons, this process is controlled by the diffusion of U-III. The diffusion coefficient of U(III) was calculated using the three electrochemical methods.