Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Reactivity of SO2 Catalytic Reduction over Sn-Zr Based Catalyst under High Pressure Condition

고압조건에서 Sn-Zr계 촉매상에서 SO2 촉매환원 반응특성

  • Park, Jung Yun (School of Chemical Engineering & Technology, Yeungnam University) ;
  • Park, No-Kuk (Institute of Clean Technology, Yeungnam University) ;
  • Lee, Tae Jin (School of Chemical Engineering & Technology, Yeungnam University) ;
  • Baek, Jeom-In (Korea Electric Power Research Institute) ;
  • Ryu, Chong Kul (Korea Electric Power Research Institute)
  • 박정윤 (영남대학교, 디스플레이화학공학부) ;
  • 박노국 (영남대학교, 청정기술연구소) ;
  • 이태진 (영남대학교, 디스플레이화학공학부) ;
  • 백점인 (한국전력공사 전력연구원) ;
  • 류청걸 (한국전력공사 전력연구원)
  • Received : 2010.02.04
  • Accepted : 2010.03.04
  • Published : 2010.06.30
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Abstract

The $SO_2$ catalytic reduction was carried out under the condition of high pressure in this study. Sn-Zr based oxide and CO were used as the catalyst and reducing agent for the reduction of $SO_2$ to element sulfur, respectively. In order to compare the reactivity with the pressure on the catalytic process, the reactivity tests were performed under the conditions of atmospheric pressure and 20 atm. $SO_2$ conversion, the element sulfur yield and COS selectivity were also compared with changing the reaction temperature, $CO/SO_2$ mole ratio and the space velocity(GHSV). $SO_2$ conversion increased with increasing temperature and $CO/SO_2$ mole ratio under the condition of atmospheric pressure and element sulfur yield decreased due to the production of COS by the series reaction of CO and the produced sulfur. However, high $SO_2$ conversion and high element sulfur were obtained under the condition of 20 atm. It was concluded that COS decreased due to the condensation of the produced element sulfur under the condition of high pressure. Therefore, the high sulfur yield for $SO_2$ catalytic reduction could be profitably obtained under the condition of high pressure.

본 연구에서는 고압조건에서 $SO_2$를 원소 황으로 전환하기 위한 촉매환원반응이 수행되었다. $SO_2$ 환원을 위한 촉매로 Sn-Zr계 금속복합산화물 촉매를 사용하였으며, 환원제로 CO가 사용되었다. 촉매환원반응성을 조사하기 위하여 반응온도, 반응물의 몰비([CO]/[$SO_2$]), 공간속도에 따른 $SO_2$ 전화율과 원소 황 수율 그리고 COS의 선택도를 상압조건과 20기압조건에서 비교되었다. 상압조건에서 $SO_2$ 전화율은 반응온도가 증가될수록 함께 증가되었으며, $CO/SO_2$ 몰비가 높을수록 증가되었다. 또한 $SO_2$ 전화율의 증가와 함께 COS의 선택도도 함께 증가되어, 원소 황 수율은 오히려 낮아졌다. 그러나 20 atm의 고압조건에서는 높은 $SO_2$ 전화율과 낮은 COS의 선택도가 얻어졌다. 이와 같은 결과는 높은 압력으로 인한 반응속도의 증가와 함께 생성된 원소 황이 응축되어 CO에 의한 COS 생성이 억제되었기 때문이라 판단된다. 이와 같은 결과로부터 $SO_2$ 촉매환원반응으로 높은 황 수율은 고압조건에서 더 유리하게 얻을 수 있다.

Keywords

References

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