Studies on the electro-reduction kinetics of uranium (VI) and nitric acid in system of 30% TBP (kerosene)-HNO3

In the study on development of in-situ uranium and plutonium electro-reduction process and equipment, the dependence of U(VI) electro-reduction rates on component concentrations has been investigated with the system UO2(NO3)2-HNO3-N2H5NO3(H2O)/30% TBP (OK). The electrolytic cell employed is a glass column with an internal diameter of 50 mm. The sieve plates are made of titanium, serving as cathode, the anodic central rod is made of platinum or stainless steel, and polyethylene material is used for the insulators between anode and cathode. The oscillation of reciprocating plate makes both phases dispersed. The U(IV) formation rates are measured under various component concentrations. The results show that the presence of hydrazine as the supporting reductant or stabilizer is necessary for the reduction of U(VI). In the range of experimental concentrations, the U(VI) reduction rates are mainly dependent on the U(VI) concentration in the system and slightly dependent on the [HNO3] and [N2H5+] concentrations. The data for the preset system are well correlated by the rate equation