Clean Technology (청정기술)

The Korean Society of Clean Technology (한국청정기술학회)
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Effect of Steam-Treated Zeolite BEA Catalyst in NH3-SCR Reaction

NH3-SCR 반응에서 스팀 처리된 zeolite BEA 촉매의 영향

  • Park, Ji Hye (Department of Chemical Engineering Education, Chungnam National University) ;
  • Cho, Gwang Hee (Graduate School of Energy Science and Technology, Chungnam National University) ;
  • Hwang, Ra Hyun (Graduate School of Energy Science and Technology, Chungnam National University) ;
  • Baek, Jeong Hun (Energy Conversion & Storage Materials Laboratory, Korea Institute of Energy Research) ;
  • Yi, Kwang Bok (Department of Chemical Engineering Education, Chungnam National University)
  • 박지혜 (충남대학교 화학공학교육과) ;
  • 조광희 (충남대학교 에너지과학기술대학원) ;
  • 황라현 (충남대학교 에너지과학기술대학원) ;
  • 백정훈 (한국에너지기술연구원 변환저장소재연구실) ;
  • 이광복 (충남대학교 화학공학교육과)
  • Received : 2020.06.06
  • Accepted : 2020.06.22
  • Published : 2020.06.30
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Abstract

Nitrous oxide (N2O) is one of the six greenhouse gases, and it is essential to reduce N2O by showing a global warming potential (GWP) equivalent to 310 times that of carbon dioxide (CO2). Selective catalytic reduction (SCR) is a technology that converts ammonia into harmless N2 and H2O by using ammonia as a reducing agent to remove NOx, one of the air pollutants; the process also produces high denitrification efficiency. In this study, the Fe-BEA catalyst was steam-treated at 100 ℃ for 2 h before Fe ion exchange in the fixed bed reactor in order to investigate the effect of the steam-treated Fe-BEA catalyst on the NH3-SCR reaction. NH3-SCR reaction test of synthesized catalysts was performed at WHSV = 180 h-1, 370 to 400 ℃ in the fixed bed reactor. The Fe-BEA(100) catalyst steam-treated at 100 ℃ showed a somewhat higher activity than the Fe-BEA catalyst at 370 to 390 ℃. The catalysts were characterized by BET, ICP, NH3-TPD, H2-TPR, and 27Al MAS NMR in order to determine the cause affecting NH3-SCR activity. The H2-TPR result confirmed that the Fe-BEA(100) catalyst had a higher reduction of isolated Fe3+ than the Fe-BEA catalyst, and that the steam treatment increased the amount of isolated Fe3+ as an active species, thus increasing the activity.

아산화질소(N2O)는 6대 온실가스 중 하나로 이산화탄소(CO2)의 310배에 해당하는 지구온난화지수(global warming potential, GWP)를 나타내어 N2O를 저감하는 것은 필수적이다. 선택적 촉매환원법(selective catalytic reduction, SCR)은 대기오염 물질의 하나인 NOx의 제거를 위해 암모니아를 환원제로 사용하여 무해한 N2 및 H2O로 전환하는 기술로 높은 탈질효율을 나타낸다. 본 연구에서는 NH3-SCR반응에서 스팀 처리된 Fe-BEA 촉매가 활성에 미치는 영향을 조사하기 위하여 Fe-BEA 촉매는 Fe를 이온교환하기 전, 고정층 반응기로 100 ℃에서 2 h 동안 스팀 처리 되었다. 제조된 촉매의 NH3-SCR반응 테스트는 고정층 반응기로 WHSV = 180 h-1, 370 ~ 400 ℃에서 수행되었다. 100 ℃에서 스팀 처리된 Fe-BEA(100) 촉매가 370 ~ 390℃에서 Fe-BEA 촉매보다 다소 높은 활성을 나타내었다. NH3-SCR 활성에 영향을 주는 원인을 파악하기 위하여 제조된 촉매는 BET, ICP, NH3-TPD, H2-TPR, 27Al MAS NMR을 통하여 특성분석 되었다. H2-TPR결과를 통해 Fe-BEA(100) 촉매가 Fe-BEA 촉매 보다 isolated Fe3+의 환원이 더 많이 일어난 것을 확인하였으며, 스팀 처리는 활성종인 isolated Fe3+의 양을 늘려주어 활성이 증가한 것으로 판단된다.

Keywords

References

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