Rare earth/transition metal alloy scrap treatment method

Abstract From the Canadian patent

A method of treating rare earth/transition metal (e.g. iron) alloy scrap involves dissolving the scrap in an aqueous mineral acid solution reacting the solution of dissolved rare earth metal and transition metal with sufficient excess HF acid to selectively precipitate the rare earth fluoride while retaining the transition metal (e.g. iron) in solution, and then separating the precipitated rare earth fluoride from the solution. The separated rare earth fluoride is dried to render it suitable for use as a reactant salt feedstock in the thermite reduction process or in other metallothermic reduction processes.