Nd Nd Highly efficient leaching method of waste Nd permanent magnets by selective oxidation heat treatment and a powder produced thereby

• Main Authors: PARK KWANG SUK, PARK HYUNG KI, KANG JANG WON, LEE TAEG WOO, SEO BO SUNG, KANG HYUN SOO, NA TAE WOOK
• Format: Patent
• Language: English; Korean
• Published: 08.06.2021
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMISTRY; ELECTRICITY; FERROUS OR NON-FERROUS ALLOYS; INDUCTANCES; MAGNETS; METALLURGY; PRETREATMENT OF RAW MATERIALS; PRODUCTION AND REFINING OF METALS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES; TRANSFORMERS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

The present invention relates to a method of highly efficient leaching of a waste Nd permanent magnet through selective oxidation heat treatment, which can obtain only final Nd_2O_3 and Fe_2O_3 through selective oxidation heat treatment without a solution process in an NdFeB magnet scrap, and Nd powder manufactured thereby. The method comprises: a step (a) of crushing the waste Nd permanent magnet; a step (b) of performing the selective oxidation heat treatment on the waste Nd permanent magnet crushed in the step (a); a step (c) of performing oxidizing roasting on the waste Nd permanent magnet which undergoes the selective oxidation heat treatment in the step (b); a step (d) of leaching the waste Nd permanent magnet with acid, wherein the magnet undergoes the oxidizing roasting in the step (c); and a step (e) of extracting a solvent. Therefore, the present invention can reduce recovery cost of Nd in the waste Nd permanent magnet. NdFeB 자석 스크랩에서 용액공정 없이, 선택적 산화 열처리만을 통해 최종 Nd2O3와 Fe2O3만을 얻을 수 있는 폐 Nd 영구자석의 고효율 침출 방법 및 이에 의해 제조된 Nd 분말에 관한 것으로, (a) 상기 폐 Nd 영구자석을 파쇄하는 단계, (b) 상기 단계 (a)에서 파쇄된 하는 단계, (c) 상기 단계 (b)에서 선택적 산화 열처리된 폐 Nd 영구자석을 산화배소 처리하는 단계, (d) 상기 단계 (c)에서 산화배소 처리된 폐 Nd 영구자석을 산으로 침출시키는 단계, (e) 용매를 추출하는 단계를 포함하는 구성을 마련하여, 폐 Nd 영구자석에서 Nd의 회수 비용을 절감할 수 있다.