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2025 Vol.34, Issue 5

Article Review

A Short Review on Hydrometallurgical Recovery of Iridium

이리듐의 습식제련 기반 회수 기술에 대한 문헌 연구

Hyein Kim1
,
Junmo Ahn1*
김 혜인1
,
안 준모1*
1Department of Mineral Resources and Energy Engineering, Jeonbuk National University, 567 Baekje-daero, Jeonju-si
1전북대학교 자원·에너지공학과
*Corresponding Author
31 October 2025. pp. 3-17
PDF XML Citation
Abstract

Ir is widely used in various industries, including chemical and electronics industry, owing to its high corrosion and heat resistance. The importance of Ir as a catalyst in proton exchange membrane electrolyzers has increased with the growing demand for green hydrogen, necessitating the recycling of secondary Ir sources, particularly owing to the scarcity of Ir and its high cost. Domestic research on hydrometallurgical recovery of Ir is limited in South Korea. This paper reviews international case studies of hydrometallurgical methods for the recovery of Ir from various Ir-containing resources. In addition, the literature concerning overseas PGMs (Platinum Group Metals) refining processes, including Ir separation, is reviewed.

Keywords
Iridium
Hydrometallurgy
PGMs
Leaching
Solvent extraction

이리듐(Iridium, Ir)은 우수한 내식성, 내열성의 특성이 있어 첨단 산업에서 주로 이용되고 있다. 최근 그린 수소 생산에 대한 수요가 증가와 함께 이리듐의 수요 또한 증가하고 있다. 특히 이리듐이 촉매로 사용되는 PEM(Proton exchange membrane) 전해조의 용량 확장이 요구되면서 Ir의 중요성이 더욱 부각되고 있다. 이리듐은 PEM 전해조 외에도 다양한 산업 분야에서 활용되고 있으나, 그 희소성과 높은 가격으로 인해 2차 금속 자원에서의 이리듐 회수를 위한 재활용 기술이 필수적이다. 하지만 국내 이리듐의 습식제련을 이용한 재활용 연구가 미비한 실정이다. 이에 본 논문은 이리듐 자원으로부터 이리듐 회수를 위한 습식제련(침출, 용매추출)에 대한 해외 연구 사례를 조사하였다. 또한 상업적 PGM 정제 공정의 이리듐 회수 사례를 조사하였다.

키워드
이리듐
습식제련
백금족 금속
침출
용매추출
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Information
  • Publisher :The Korean Institute of Resources Recycling
  • Publisher(Ko) :한국자원리싸이클링학회
  • Journal Title :Resources Recycling
  • Journal Title(Ko) :자원리싸이클링
  • Volume : 34
  • No :5
  • Pages :3-17
  • Received Date : 2025-07-25
  • Revised Date : 2025-08-23
  • Accepted Date : 2025-09-02
  • DOI :https://doi.org/10.7844/kirr.2025.34.5.3
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