Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Recent Progress in the Catalytic Decomposition of Methane in a Fluidized Bed for Hydrogen and Carbon Material Production

수소 및 탄소소재 생산을 위한 메탄 유동층 촉매분해 기술의 최근 동향

  • Keon Bae (Hydrogen Research Department, Korea Institute of Energy Research) ;
  • Kang Seok Go (Energy Resources Upcycling Research Laboratory, Korea Institute of Energy Research) ;
  • Woohyun Kim (Hydrogen Research Department, Korea Institute of Energy Research) ;
  • Doyeon Lee (Department of Civil and Environmental Engineering, Hanbat National University)
  • 배건 (한국에너지기술연구원 수소연구단) ;
  • 고강석 (한국에너지기술연구원 에너지자원순환연구실) ;
  • 김우현 (한국에너지기술연구원 수소연구단) ;
  • 이도연 (한밭대학교 건설환경공학과)
  • Received : 2022.11.24
  • Accepted : 2023.01.13
  • Published : 2023.05.01
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Abstract

Global interest in hydrogen energy is increasing as an eco-friendly future energy that can replace fossil fuels. Accordingly, a next-generation hydrogen production technology using microorganisms, nuclear power, etc. is being developed, while a lot of time and effort are still required to overcome the cost of hydrogen production based on fossil fuels. As a way to minimize greenhouse gas emissions in the hydrocarbon-based hydrogen production process, methane direct decomposition technology has recently attracted attention. In order to improve the economic feasibility of the process, the simultaneous production of value-added carbon materials with hydrogen can be one of the most essential aspects. For that purpose, various studies on catalysis related to the quality and yield of high-value carbon materials such as carbon nanotubes (CNTs). In terms of process technology, a number of the research and development of fluidized-bed reactors capable of continuous production and improved gas-solid contact efficiency has been attempted. Recently, methane direct decomposition technology using a fluidized bed has been developed to the extent that it can produce 270 kg/day of hydrogen and 1000 kg/day of carbon. Plus, with the development of catalyst regeneration, separation and recirculation technologies, the process efficiency can be further improved. This review paper investigates the recent development of catalysts and fluidized bed reactor for methane direct pyrolysis to identify the key challenges and opportunities.

화석연료를 대체할 수 있는 친환경 미래 에너지로 수소에너지에 대한 전세계적 관심이 높아지고 있다. 이에 따라 미생물, 원자력 등을 이용한 차세대 수소 생산 기술이 개발되고 있으나, 화석연료 기반의 수소 생산 비용을 뛰어 넘기에는 아직 많은 시간과 노력이 필요한 상황이다. 화석연료 기반의 수소 생산 과정에서 온실가스의 배출량을 최소화 할 수 있는 방안으로 메탄 직접분해 반응 기술이 최근 관심을 모으고 있다. 공정의 경제성 향상을 위해서 수소 생산과 동시에 생산된 탄소물질의 고부가화 대한 연구가 필수적이며, 고부가 탄소 물질 중 하나인 탄소나노튜브(Carbon nanotube, CNT)의 품질 및 수율 등과 관련한 촉매반응 연구가 지속되어 왔다. 또한 공정기술 측면에서, 연속적인 생산이 가능하며 기체-고체 접촉 효율이 좋은 유동층 공정을 적용시켜 생산성과 경제성을 확보하고자 하는 연구가 시도되었다. 최근 유동층을 이용한 메탄 직접분해 반응기술은 수소 270 kg/day, 탄소 1000 kg/day의 생산이 가능한 정도의 기술 개발이 진행되었으며, 향후 촉매 재활성화, 분리 및 재순환 기술 등이 개발되면 공정의 효율이 크게 제고될 것이다. 이에 본 총설에서는 메탄 직접 분해에 활용되는 촉매 및 유동층 메탄 열분해 기술의 최근 연구들을 고찰하였다.

Keywords

Acknowledgement

본 연구는 한국에너지기술연구원의 기본사업(C2-2480, C3-2421)을 재원으로 수행한 연구과제의 결과입니다. 또한, 2022년도 산업통상자원부 및 산업기술평가관리원(KEIT) 연구비 지원(연구개발과제번호: 20010853)에 의한 연구입니다.

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