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2025 Vol.34, Issue 6 Preview Page

Research Paper

Experimental Study on Flotation-Chemical Purification for High-Purity Graphite Production from Domestic Natural Graphite Ore

국내 천연 흑연광의 고순도 흑연 생산을 위한 부유선별-화학적 정제에 대한 실험적 연구

Serin Kang12
,
Jaemin Ahn1
,
Donghyun Kim1
,
Seongmin Kim1
,
Seongsoo Han13
,
Wonjae Lee1
,
Seungwook Shin4
,
Ki Min Roh1
,
Haesung Jeong2
,
Yosep Han13*
강 세린12
,
안 재민1
,
김 동현1
,
김 성민1
,
한 성수13
,
이 원재1
,
신 승욱4
,
노 기민1
,
정 해성2
,
한 요셉13*
1Resources Utilization Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), 124 Gwahak-ro, Yuseong-gu, Daejeon 34132, Republic of Korea
2Department of Chemical Engineering Changwon National University, Changwon 51140, Republic of Korea
3Resources Engineering, University of Science Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, Republic of Korea
4Mineral Resources Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), 124 Gwahak-ro, Yuseong-gu, Daejeon 34132, Republic of Korea
1한국지질자원연구원 자원활용연구본부
2국립창원대학교 이차전지화학공학과
3과학기술연합대학원대학교 KIGAM 스쿨 자원공학
4한국지질자원연구원 광물자원연구본부
*Corresponding Author
31 December 2025. pp. 70-81
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Abstract

This study investigated the production of high-purity graphite from natural graphite ore collected in Geumam, Dangjin, Korea. The ore was processed using a combined flotation and acid purification process involving sulfuric acid (H2SO4) and hydrofluoric acid (HF). A conventional, multi-stage flotation process yielded a graphite concentrate with an approximate grade of 70 %. Purification experiments were then conducted under various H2SO4 (0.05-5.0 M) and HF (0.05-5.0 M) concentrations to evaluate their effect on purification performance. The results showed that H2SO4 treatment alone had little effect on enhancing the purity, whereas carbon content significantly increased with higher concentrations of HF, achieving over 99.9 % purity at a concentration of 5.0 M. SEM-EDS analysis confirmed that silicon (Si), aluminum (Al), and iron (Fe) impurities were almost completely removed under high-HF conditions. Particle size analysis revealed a more uniform distribution after chemical purification. These findings suggest that HF plays a dominant role in impurity removal from SiO2-rich siliceous graphite ores compared to H2SO4.

Keywords
Natural graphite ore
flotation
chemical purification
high-purity graphite

본 연구는 충청남도 당진시 금암 지역에서 채취한 천연 흑연광을 대상으로 부유선별과 황산-불산을 활용한 화학적 정제 공정으로부터 고순도 흑연 제조 가능성을 실험적으로 검토하였다. 다단 부유선별 공정을 적용한 결과, 총 탄소 함량 70 wt.%의 정광을 얻었다. 이후, 화학적 정제를 통하여 고순도 흑연 생산 특성을 평가하기 위해 황산과 불산의 다양한 농도로 설정하여 실험을 수행하였다. 이에 황산(0.05-5.0 M) 및 불산(0.05-5.0 M) 농도를 변화시켜 정제 거동을 비교한 결과, 황산 단독 처리에서는 순도 향상이 거의 없었으나, 불산 농도가 증가함에 따라 탄소 함량이 급격히 상승하였고 5.0 M HF 조건에서 99.9 % 이상의 고순도 흑연을 얻을 수 있었다. SEM–EDS 분석 결과, 고농도 HF 처리 시 Si, Al, Fe 성분 등이 제거되었으며, 입도분석에서도 화학 정제 후 입자 크기가 균일해지는 경향을 나타내었다. 이러한 결과는 SiO2 함량이 높은 규산염계 흑연광의 특성으로 인해 황산보다 불산이 정제에 미치는 효과가 더 큰 것으로 파악된다.

키워드
천연 흑연광
부유선별
화학적 정제
고순도 흑연
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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 :6
  • Pages :70-81
  • Received Date : 2025-11-10
  • Revised Date : 2025-12-12
  • Accepted Date : 2025-12-17
  • DOI :https://doi.org/10.7844/kirr.2025.34.6.70
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