Abstract
In recent years, the production of rare earth permanent magnets is increasing in Japan, and the quantity of disposal is also increasing. The recycling of wastes generated in the manufacturing process is technically established. However, the used magnets included in municipal solid wastes have not been recycled. As all of rare earth raw materials are imported in Japan, resource recovery from rare earth magnets is necessary. In the present study, the recovery of Nd from Nd-Fe-B magnet by hydrothermal treatment in several kinds of acid solvents was investigated. As a result, it was found that about 99% of Nd included in Nd-Fe-B bulk magnet was selectively extracted by the hydrothermal treatment in HCl-(COOH)2 aqueous solution.
