The SO₂ Resistance Improvement of Mn‐Fe/ZSM‐5 for NH₃‐SCR at Low Temperature by Optimizing Synthetic Method

Abstract

Mn‐Fe/ZSM‐5 was prepared via co‐precipitation (CP) and precipitation–chemical vapor deposition (P‐CVD) methods. Catalytic performance investigation showed that Mn‐Fe/ZSM‐5 by P‐CVD method had higher catalytic activity and SO2 resistance than the ones by CP method for NH3‐SCR at low temperature. Characterization results proved that the amount of ammonium sulfate deposited on the surface of Mn‐Fe/ZSM‐5(P‐CVD) was less than that of Mn‐Fe/ZSM‐5(CP) catalyst. Further investigations revealed that the deposition and decomposition of ammonium sulfate proceeded in a dynamic balance on Mn‐Fe/ZSM‐5(P‐CVD) catalyst, which was crucial for the excellent catalytic performances in the presence of SO2 and H2O.

The Resistance of SO2 and H2O of Mn-Based Catalysts for NOx Selective Catalytic Reduction with Ammonia: Recent Advances and Perspectives

“…After adding 30 ppm of SO 2 to inlet flue gas at 120 °C, the NO conversion rate of ordinary Mn/TiO 2 drops sharply from 57 to 15% within 6 h, while the NO conversion rate of HM Mn/TiO 2 remains above 84%. Zou et al 106 prepared Mn-Fe/ZSM-5 catalysts by coprecipitation and precipitation–chemical vapor deposition methods. The Mn-Fe/ZSM-5 catalyst obtained by method B had higher SO 2 resistance.…”