	US 12,146,225 B2
	Method for recycling rare earth sintered magnet
Ko Watanabe, Fukui (JP); Kazuhito Akada, Echizen (JP); Yuta Kuribara, Makati (PH); and Yoshiyuki Hayashi, Fukui (JP)
Assigned to SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
Filed by SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
Filed on Jul. 7, 2022, as Appl. No. 17/859,441.
Claims priority of application No. 2021-114321 (JP), filed on Jul. 9, 2021.
Prior Publication US 2023/0029439 A1, Jan. 26, 2023
Int. Cl. C23F 1/40 (2006.01); C22B 1/00 (2006.01); C23F 1/44 (2006.01)

CPC C23F 1/40 (2013.01) [C22B 1/005 (2013.01); C23F 1/44 (2013.01)]

7 Claims

1. A method for recycling a rare earth magnet, the method comprising:

immersing a rare earth magnet having a film comprising Ni on the surface thereof in a stripping solution comprising a derivative of nitrobenzene, ethylenediamine, and ammonia,

wherein a stripping tank storing the solution has a barrel rotating mechanism, a barrel of the barrel rotating mechanism contains the rare earth magnet and chemical resistant spheres, and a number of revolutions per minute of the barrel rotating mechanism is 10 rpm or less.