Uranium Purification by Electrorefining

Abstract

The feasibility of a high temperature electrorefining process for decontamination of U from associated fission products was demonstrated. Low-melting alloys of U with Ni were used to obtain molten products at temperatures below the melting point of pure U. Effects of temperature, current, and salt-bath composition on cell efficiency and cell operation are discussed.

Electroformation of uranium hemispherical shells

“…The discrepancy between the consumed and recovered charges in these plating experiments indicates the presence of a parasitic electrode reaction, which becomes progressively more important as the cathodic overvoltage reaches more negative values. This is in agreement with results obtained by Niedrach and Glamm, 4 who observed a decrease in current efficiency with increasing current under galvanostatic conditions. The explanation proposed by these authors was that the parasitic reaction is the reduction of UC1 4 to UCl 3 at the cathode.…”

“…This is in agreement with results obtained by Niedrach and Glamm, 4 who observed a decrease in current efficiency with increasing current under galvanostatic conditions. The explanation proposed by these authors was that the parasitic reaction is the reduction of UC1 4 to UCl 3 at the cathode. In view of the high purity of the electrolyte starting materials and the glovebox atmosphere used in our work, this indeed seems the most reasonable explanation.…”

“…As the cathodic polarization of the working electrode increases, the resulting increase in the anodic polarization of the counter electrode could result in the further oxidation of UCl 3 to UC1 4 . Diffusion of this UC1 4 through the electrolyte, followed by its reduction to UCl 3 at the working electrode, would conu"me some of the charge that would otherwise result in the deposition of uranium.…”

“…Although UCl 3 is the thermodynamically preferred species, 4 an assessment of the role of UC1 4 in electrodeposition would require knowledge of the rate of this non-electrochemical reaction, in addition to the kinetic parameters of the U/U 3 + and U 3 +/U 4 + electrode reactions.…”

“…Electrolytic preparation was also performed during the Manhattan Project 2 and subsequently adapted to the refinement of uranium produced by nonelectrochemical methods" and nuclear fuel reprocessing. 4 While several potentiometric studies of U/U 3 + (Refs. 5-7) and U 3 +/U 4 + (Refs.…”