화학공학소재연구정보센터
Clean Technology, Vol.24, No.4, 307-314, December, 2018
망간산화물(NMO, MnO2, Mn2O3)을 이용한 저온에서의 NH3-SCR의 반응속도 연구
A Reaction Kinetic for Selective Catalytic Reduction of NOx with NH3 over Manganese Oxide (NMO, MnO2, Mn2O3) at Low Temperature
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초록
본 연구에서는 NMO (Natural Manganese Ore), MnO2, Mn2O3 촉매를 산소 존재 하에 저온에서 NH3를 환원제로 이용하여 질소산화물(NOx)을 제거하는 선택적 촉매 환원법에 사용되었다. NMO의 경우, 안정성 실험에서 질소산화물 전환율이 423 K에서 100시간 후에도 변하지 않는 것을 확인하였다. 동력학 실험의 경우, 열 및 물질전달이 영향을 주지 않는 영역에서 수행하였다. 정상상태에서의 반응속도 연구는 저온 SCR반응에서 암모니아에 대하여 0차이고 일산화질소에 대해서는 0.41 ~0.57차였으며 산소에 대해서는 0.13 ~ 0.26차인 것을 확인하였다. 온도가 증가할 때, 암모니아와 산소 농도의 결과에 따라 반응차수가 감소함을 확인하였다. 촉매 표면에 해리흡착 된 암모니아와 가스상 일산화질소(E-R 모델)와의 반응 및 흡착 된 일산화질소(L-H 모델)와의 반응을 확인하였다.
In this study, NMO (Natural Manganese Ore), MnO2, and Mn2O3 catalysts were used in the selective catalytic reduction process to remove nitrogen oxides (NOx) using NH3 as a reducing agent at low temperatures in the presence of oxygen. In the case of the NMO (Natural Manganese Ore), it was confirmed that the conversion of nitrogen oxides in the stability test did not change even after 100 hours at 423 K. The Kinetics experiments were carried out within the range where heat and mass transfer were not factors. From a steady-state Kinetics study, it was found that the low-temperature SCR reaction was zero order with the respect to NH3 and 0.41 ~ 0.57 order with the respect to NO and 0.13 ~ 0.26 order with the respect to O2. As temperature increases, the reaction order decreases as a result of NH3 and oxygen concentration. It was confirmed that the reaction between the NH3 dissociated and adsorbedon the catalyst surface and the gaseous nitrogen monoxide (E-R model) and the reaction with the adsorbed nitrogen monoxide (L-H model) occur.
  1. Bosch H, Janssen F, Catal. Today, 2, 369 (1988)
  2. Wood SC, Chem. Eng. Prog., 90(1), 32 (1994)
  3. Cho SM, Eng. Prog., 90, 39 (1994)
  4. Forzatti P, Heterogen LL, Chem. Rev., 3, 33 (1996)
  5. Alemany LJ, Berti F, Busca G, Ramis G, Robba D, Toledo GP, Trombetta M, Appl. Catal. B: Environ., 10(4), 299 (1996)
  6. Rahkamaa-Tolonen K, Maunula T, Lomma M, Huuhtanen M, Keiski RL, Catal. Today, 100(3-4), 217 (2005)
  7. Qi GS, Yang RT, Appl. Catal. B: Environ., 60(1-2), 13 (2005)
  8. Sjo vall H, Blint RJ, Gopinath A, Olsson L, Ind. Eng. Chem. Res., 49, 39 (2009)
  9. Ma AZ, Grunert W, Chem. Commun., 71 (1999).
  10. Long RQ, Yang RT, Catal. Lett., 74(3-4), 201 (2001)
  11. Park TS, Jeong SK, Hong SH, Hong SC, Ind. Eng. Chem. Res., 40(21), 4491 (2001)
  12. Tang X, Hao J, Xu W, Li J, Catal. Commun., 8, 329 (2007)
  13. Kang M, Park ED, Kim JM, Yie JE, Appl. Catal. A: Gen., 327(2), 261 (2007)
  14. Kang M, Park JH, Choi JS, Park ED, Yie JE, J. Chem. Eng., 24, 191 (2007)
  15. Kang M, Yeon TH, Park ED, Yie JE, Kim JM, Catal. Lett., 106(1-2), 77 (2006)
  16. Kapteijn F, Singoredjo L, Andreini A, Moulijn JA, Appl. Catal. B: Environ., 3(2-3), 173 (1994)
  17. Dekker FH, Bliek A, Kapteijn F, Moulijn JA, Chem. Eng. Sci., 50(22), 3573 (1995)
  18. Bosch H, Janssen F, Catal. Today, 2, 433 (1988)
  19. Qi GS, Yang RT, Appl. Catal. B: Environ., 44(3), 217 (2003)
  20. Turco M, Lisi L, Pirone R, Ciambelli P, Appl. Catal. B: Environ., 3(2-3), 133 (1994)
  21. Huang HY, Long RQ, Yang RT, Appl. Catal. A: Gen., 235(1-2), 241 (2002)
  22. Iwasaki M, Yamazaki K, Shinjoh H, Appl. Catal. A: Gen., 366(1), 84 (2009)