Electrochemical separation of aluminum from uranium for research reactor spent nuclear fuel applications

• Published in: Separation and purification technology Vol. 15; no. 3; pp. 197 - 205
• Main Authors: Slater, S.A, Raraz, A.G, Willit, J.L, Gay, E.C
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 03.05.1999; Elsevier Science
• Subjects: ALLOYS; ALUMINIUM; Aluminum-based spent nuclear fuel; ANL; ANODES; Applied sciences; CRUCIBLES; ELECTROCHEMICAL CELLS; Electrochemical separation; ELECTROLYTES; ELECTROREFINING; Energy; Exact sciences and technology; Fluoride salt electrolyte; FLUORIDES; Fuels; High throughput electrorefiner; NUCLEAR FUEL CYCLE AND FUEL MATERIALS; NUCLEAR FUELS; Pollution; Preparation and processing of nuclear fuels; Radioactive wastes; RARE EARTHS; RESEARCH REACTORS; URANIUM; URANIUM 228; Wastes; High throughput electrorefiner; Uranium; Electrochemical separation; Fluoride salt electrolyte; Aluminum-based spent nuclear fuel; Spent fuels; Electrochemical method; Separation process; Electrorefining; Aluminium; Nuclear fuel; Fluorides; Fused salt electrolyte; Reprocessing; Optimization; Irradiated nuclear fuel
• ISSN: 1383-5866; 1873-3794
• DOI: 10.1016/S1383-5866(98)00101-4

Researchers at Argonne National Laboratory (ANL) are developing an electrorefining process to treat aluminum-based spent nuclear fuel by electrochemically separating aluminum from uranium. The aluminum electrorefiner is modeled after the high-throughput electrorefiner developed at ANL. Aluminum is electrorefined, using a fluoride salt electrolyte, in a potential range of −0.1 V to −0.2 V, while uranium is electrorefined in a potential range of −0.3 V to −0.4 V; therefore, aluminum can be selectively separated electrochemically from uranium. A series of laboratory-scale experiments was performed to demonstrate the aluminum electrorefining concept. These experiments involved selecting an electrolyte (determining a suitable fluoride salt composition); selecting a crucible material for the electrochemical cell; optimizing the operating conditions; determining the effect of adding alkaline and rare earth elements to the electrolyte; and demonstrating the electrochemical separation of aluminum from uranium, using a U–Al–Si alloy as a simulant for aluminum-based spent nuclear fuel. Results of the laboratory-scale experiments indicate that aluminum can be selectively electrotransported from the anode to the cathode, while uranium remains in the anode basket.