Fundamental Study on the Separation Characteristics of Cathode,  Anode,  and Lithium from Black Mass with the NMC Reduction in Spent Lithium-Ion Batteries

Chanwoo Yang; Kwangsuk You; Kwanho Kim; Gilsang Hong

doi:10.7844/kirr.2026.35.1.66

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2026 Vol.35, Issue 1 Preview Page Next Page

Research Paper

Fundamental Study on the Separation Characteristics of Cathode, Anode, and Lithium from Black Mass with the NMC Reduction in Spent Lithium-Ion Batteries 사용 후 배터리의 양극재 환원 반응에 따른 블랙매스 양극재와 음극재 및 리튬의 분리·선별 특성 기초 연구

28 February 2026. pp. 66-75

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Abstract

In the recycling of spent lithium-ion batteries, the pretreatment process for recovering black mass generally consists of crushing and grinding, heat treatment to remove organic materials, and separation and classification to remove impurities. During heat treatment, depending on the heating temperature, the removal of organics, cathode reduction and lithium phase transformation can occur simultaneously. Therefore, this study discusses the fundamental separation characteristics of the cathode, anode, and lithium in a black mass associated with phase changes at the cathode reduction temperature. For this purpose, black mass was heat-treated at 550 ℃ for 2h under an N₂ atmosphere, and the flotation and magnetic separation characteristics of the cathode and anode materials, as well as lithium leaching characteristics in aqueous solution, were examined. The results confirmed the removal of organics and the reduction of the cathode material. Compared to untreated black mass, the separation efficiency increased by approximately 43.9% in flotation and 69.3% in magnetic separation. In addition, aqueous leaching tests demonstrated that approximately 76.4% of the Li in the black mass was leached. These findings indicate that reductive heat treatment can significantly enhance the separation efficiency between the cathode and anode while enabling lithium recovery in the aqueous phase. The results of this study are expected to serve as fundamental data for developing optimal processes for separating the cathode, anode, and lithium from black mass under various heat-treatment conditions.

Keywords

Black Mass

Thermal treatment

Flotation

Magnetic separation

Lithium carbonation

사용 후 배터리로부터 블랙매스를 회수하는 전처리 공정은 일반적으로 파·분쇄 공정, 유기물 제거를 위한 열처리 공정, 그리고 불순물 제거를 위한 선별·분급 공정으로 구성된다. 이 중 열처리 단계에서는 가열 온도에 따라 유기물 제거뿐 아니라 양극재의 환원 반응과 리튬의 상 전환 반응이 동시에 일어난다. 이에 본 연구에서는 블랙매스 내 양극재의 환원 반응 온도에서 양극재와 음극재, 그리고 리튬의 상변화에 따른 분리·선별 기초 특성을 논하고자 한다. 이를 위해 본 연구에서는 질소 분위기 550 ℃에서 2시간 열처리한 블랙매스를 대상으로 양극재–음극재의 부유선별 및 자력선별 특성과 리튬의 수용액 용출 특성을 검토하였다. 실험 결과, 열처리를 통해 유기물 제거와 양극재의 환원 반응이 확인되었으며, 열처리를 하지 않은 블랙매스 대비 부유선별 및 자력선별의 선별효율이 각각 약 43.9%, 약 69.3% 증가하였다. 또한 용출 실험에서 블랙매스 내 리튬의 약 76.4%가 용출되었다. 즉, 환원 열처리는 양극재–음극재의 선별효율을 유의미하게 향상시키는 동시에 리튬의 수용액 회수를 가능하게 함을 시사한다. 본 연구에서 도출된 결과는 향후 열처리 조건에 따른 블랙매스의 양극재-음극재 및 리튬의 최적 분리·선별 공정 개발을 위한 핵심 기초 자료로 활용될 수 있을 것이다.

키워드

블랙매스

열처리

부유선별

자력선별

리튬 탄산화

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Information

Publisher :The Korean Institute of Resources Recycling
Publisher(Ko) :한국자원리싸이클링학회
Journal Title :Resources Recycling
Journal Title(Ko) :자원리싸이클링
Volume : 35
No :1
Pages :66-75
Received Date : 2025-11-25
Revised Date : 2025-12-26
Accepted Date : 2026-01-06
DOI :https://doi.org/10.7844/kirr.2026.35.1.66

Resources Recycling ISSN:2765-3439(Print) 2765-3447(Online) 자원리싸이클링

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