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Reaction Mechanism of Low Temperature NH3 SCR over MnOx/Sewage Sludge Char

MnOx/Sewage Sludge Char를 이용한 저온 NH3 SCR의 반응 메커니즘

  • Cha, Jin-Sun (School of Environmental Engineering, University of Seoul) ;
  • Park, Young-Kwon (School of Environmental Engineering, University of Seoul) ;
  • Park, Sung Hoon (Department of Environmental Engineering, Sunchon National University) ;
  • Jeon, Jong-Ki (Department of Chemical Engineering, Kongju National University)
  • 차진선 (서울시립대학교 환경공학부) ;
  • 박영권 (서울시립대학교 환경공학부) ;
  • 박성훈 (순천대학교 환경공학과) ;
  • 전종기 (공주대학교 화학공학과)
  • Received : 2011.03.18
  • Accepted : 2011.03.25
  • Published : 2011.06.10

Abstract

The reaction mechanism of selective catalytic reduction of NOx over sewage sludge char impregnated with MnOx using $NH_3$ as the reducing agent was investigated. The active Mn phase was shown to be $Mn_3O_4$ from the XRD analysis. Adsorption was the dominant NOx removal mechanism at low temperatures below $150^{\circ}C$ although reduction reaction also contributed partly to the NOx removal at $100{\sim}150^{\circ}C$. The reaction rate constants of NOx removal over non-impregnated and MnOx-impregnated active chars were compared based on experimental results. The MnOx-impregnated char was shown to have a higher reaction rate constant and a higher NOx removal efficiency due to a higher collision coefficient and a lower activation energy. The activation energy for both chars was shown to be relatively low (10~12 kJ/mol) under the experimental conditions of this study.

하수슬러지 촤에 MnOx를 담지한 촉매를 사용하여 $NH_3$를 환원제로 하는 선택적 촉매 환원반응의 반응 메커니즘 분석을 수행하였다. XRD 분석 결과 활성 Mn phase는 $Mn_3O_4$인 것으로 여겨졌다. 또한 $150^{\circ}C$ 이하에서는 흡착반응이 주요한 질소산화물 저감 메커니즘으로 작동하였으나, $100{\sim}150^{\circ}C$에서는 환원반응도 질소산화물 저감에 관여하는 것으로 보여졌다. 실험결과에 기초하여 활성 촤와 여기에 MnOx를 담지한 촤에서의 반응속도상수를 비교하였다. MnOx 담지촤는 높은 충돌계수와 낮은 활성화 에너지에 기인하여 높은 반응속도 상수와 높은 NOx 제거 효율을 나타내었다. 두 가지 촤 모두 본 실험 조건하에서 활성화 에너지는 상대적으로 낮았다(10~12 kJ/mol).

Keywords

References

  1. J. C. Choi, C. H. Cho, K. E. Jeong, J. K. Jeon, J. H. Yim, and Y. K. Park, J. Kor. Ind. Eng. Chem., 19, 92 (2008).
  2. F. Nakajima and I. Hamada, Catal. Today., 29, 109 (1996). https://doi.org/10.1016/0920-5861(95)00288-X
  3. P. A. Lowe and J. N. Armor, ACS Symp. Series., 552, 205 (1994).
  4. O. Ioannidou and A. Zabaniotou, Renew. Sustain. Energy Rev., 11, 1966 (2007). https://doi.org/10.1016/j.rser.2006.03.013
  5. G. Lopez, M. Olazar, M. Artetxe, M. Amutio, G. Elordi, and J. Bilbao, J. Anal. Appl. Pyrolysis, 85, 539 (2009). https://doi.org/10.1016/j.jaap.2008.11.002
  6. J. S. Cha, J. C. Choi, J. H. Ko, Y. K. Park, S. H. Park, K. E. Jeong, S. S. Kim, and J. K. Jeon, Chem. Eng. J., 156, 321 (2010). https://doi.org/10.1016/j.cej.2009.10.027
  7. Y. B. Jo, J. S. Cha, J. H. Ko, M. C. Shin, S. H. Park, J. K. Jeon, S. S. Kim, and Y. K. Park, Korean J. Chem. Eng., 28, 106 (2011). https://doi.org/10.1007/s11814-010-0283-7
  8. G. Marban, T. V. Solis, and A. B. Fuertes, J. Catal., 226, 138 (2004). https://doi.org/10.1016/j.jcat.2004.05.022
  9. Z. Zhu, Z. Liu, S. Liu, and H. Niu, Fuel, 79, 651 (2000). https://doi.org/10.1016/S0016-2361(99)00192-1
  10. J. Muniz, G. Marban, and A. B. Fuertes, Appl. Catal. B: Environ., 27, 27 (2000). https://doi.org/10.1016/S0926-3373(00)00134-X
  11. E. Garcia-Bordeje, L. Calvillo, M. J. Lazaro, and R. Moliner, Appl. Catal. B: Environ., 50, 235 (2004). https://doi.org/10.1016/j.apcatb.2004.01.008
  12. A. Boyano, M. E. Galvez, M. J. Lazaro, and R. Moliner, Carbon, 44, 2399 (2006). https://doi.org/10.1016/j.carbon.2006.05.032
  13. M. Koebel and M. Elsener, Chem. Eng. Sci., 53, 657 (1998). https://doi.org/10.1016/S0009-2509(97)00342-4
  14. G. Marban and A. B. Fuertes, Catal. Lett., 84, 13 (2002). https://doi.org/10.1023/A:1021008113948
  15. F. Kapteijn, L. Singoredjo, N. J. J. Dekker, and J. A. Moulijn, Ind. Eng. Chem. Res., 32, 445 (1993). https://doi.org/10.1021/ie00015a007