Reprocessing of spent hydrogen absorbing alloys by using electrochemical techniques in molten salts Original Research Article

Rare earths separation from hydrogen absorbing alloys by using molten salt media is proposed. The procedure consists of the following three electrochemical techniques. (1) Rare earths are anodically electro-dissolved into ionic melt bath from spent hydrogen absorbing alloys. (2) Rare earth cations are then concentrated near the anode area into the column by using the countercurrent electromigration method. (3) Rare earths are finally cathodically electro-deposited in metallic form. Several electrochemical measurements were studied in the molten salts containing rare earth chlorides condition, and the electro-deposition was tested to check the feasibility of processes (1) and (3). Rare earths could be separable anodically from hydrogen absorbing LaNi5 alloy by using electrochemical techniques.