Electrolytic Preparation of Vanadium from Vanadium Carbide

The preparation of vanadium by molten‐salt electrolysis of a commercial vanadium carbide (VC) containing 84% vanadium was investigated. An electrolytic process was developed for the extraction of vanadium from electrolyte contained in a helium‐atmosphere cell at 650°C. The effects of electrolyte composition, vanadium depletion of the VC, and cathode current densities on the process, as well as the effects on the quality of vanadium products, were determined. Vanadium of 99% purity was prepared with an 85% recovery of vanadium and a cathode current efficiency of 70%. The vanadium contained approximately 0.60% oxygen and had a 100 Rockwell B hardness. High‐purity, ductile vanadium was prepared from the VC by electrorefining the extraction products in a separate cell or by combining the extraction and electrorefining processes in a single cell. In the combined process, the vanadium was first extracted from the VC and deposited on a cylindrical electrode; this vanadium was then electrorefined and deposited on a central cathode rod. Both methods yielded vanadium of 99.9% purity with 35–40 Rockwell B hardness. With limited tests in the combined process, 58% recovery of ductile vanadium from the VC was achieved.