Selective catalytic reduction of NO by ammonia over Fe-ZSM-5 catalysts

Abstract

In the selective catalytic reduction (SCR) of NO by ammonia, over-exchanged Fe-ZSM-5 prepared by sublimation of FeCl₃ into H-ZSM-5, shows superior catalytic activity and stability in a wide temperature range; its activity is promoted by the presence of water in the feed while SO₂ is a weak poison at low but a promoter at high temperatures; its remarkable durability towards H₂O and SO₂ makes this zeolite catalyst a potential choice in Denox applications for stationary sources and heavy Diesel engines with ammonia or urea reductants.

References

1. W. Held, A. König, T. Richter and L. Puppe, SAE-Pap., 1990, 900496.
2. M. Iwamoto, H. Yahiro, S. Shundo, Y. Yu-u and N. Mizuno, Shokubai, 1990, 32, 430.
3. M. Shelef, Chem. Rev., 1995, 95, 209.
4. J. A. Sullivan, J. Cunningham, M. A. Morris and K. Keneavey, Appl. Catal. B, 1995, 7, 137.
5. X. Feng and W. K. Hall, Catal. Lett., 1996, 41, 45.
6. W. K. Hall, X. Feng, J. Dumesic and R. Watwe, Catal. Lett., 1998, 52, 13.
7. H.-Y. Chen and W. M. H. Sachtler, Catal. Today, 1998, 42, 73.
8. M. Iwamoto, H. Yahiro, Y. Mine and S. Kagawa, Chem. Lett., 1989, 213.
9. A.-Z. Ma, F. Heinrich and W. Grünert, to be published.
10. A. V. Salker, B. Maurer and W. Weisweiler, Chem.-Ing.-Technol., 1998, 70, 566.