Green Ce-based honeycomb catalyst with excellent water and sulfur dioxide resistances for low-temperature selective catalytic reduction of NOx with ammonia

Low-temperature selective catalytic reduction (SCR) is effective and promising for converting NOx in flue gas into N-2, with wide application prospects. However, low-temperature denitration (DeNO(x)) catalysts are susceptible to SO2 and H2O poisoning. Here, we prepared a monolithic Mn-Fe-Ce/Al2O3 catalyst that exhibited excellent DeNO(x) performances at low temperatures. At 110 degrees C, the NO conversion rate of the catalyst was > 90%, exhibiting excellent resistances to H2O and SO2 center dot H2O and SO2 are introduced at the same time, the efficiency is as high as 73%. Furthermore, The catalyst has a porous structure with abundant chemisorbed oxygen spices and exposed active, the reaction pathway on the catalyst proved to be the L-H mechanism based on in situ DRIFTS. This study also explored the mechanisms of low-temperature SCR catalyst poisoning by SO2 and H2O, providing insights into the effects of SO2 and H2O and theoretical support for the development of poisoning-resistant low-temperature SCR catalysts. (C) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.

Automated summary

Low-temperature selective catalytic reduction (SCR) is an effective method for converting NOx in flue gas into N-2, but low-temperature denitration (DeNO(x)) catalysts are susceptible to SO2 and H2O poisoning. In this study, a monolithic Mn-Fe-Ce/Al2O3 catalyst was prepared, which exhibited excellent DeNO(x) performances at low temperatures and showed resistance to H2O and SO2. The catalyst has a porous structure with abundant chemisorbed oxygen species and active sites, and the L-H mechanism was proved to be the reaction pathway on the catalyst.