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

Abstract

Low-temperature selective catalytic reduction (SCR) is effective and promising for converting NOx in flue gas into N2, with wide application prospects. However, low-temperature denitration (DeNOx) catalysts are susceptible to SO2 and H2O poisoning. Here, we prepared a monolithic Mn-Fe-Ce/Al2O3 catalyst that exhibited excellent DeNOx performances at low temperatures. At 110 °C, the NO conversion rate of the catalyst was> 90%, exhibiting excellent resistances to H2O and SO2·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.