(521ep) Promoting the Enhancement of Low-Temperature Activity and N2 Selectivity for NH3-SCR Catalysts Via Changing the Interaction between Fe-Mn Sites
AIChE Annual Meeting
2023
2023 AIChE Annual Meeting
Catalysis and Reaction Engineering Division
Poster Session: Catalysis and Reaction Engineering (CRE) Division
Wednesday, November 8, 2023 - 3:30pm to 5:00pm
Manganese modified Fe2O3 catalyst is an effective way to replace the traditional commercial NH3-SCR catalyst to achieve low temperature and high selectivity removal of NOx to N2 from gas emission of fixed sources. In order to clarify the influence mechanism of different interaction modes between Mn and Fe on the NOx conversion and N2 selectivity of catalysts at low temperature, Mn doped Fe2O3 and MnO2 loaded Fe2O3 are prepared by co-precipitation method and impregnation method respectively. It is demonstrated that the doped Mn cations can provide more Lewis acid sites and more abundant Mn4+ species, which lead to the improvement of NOx conversion at low temperature. Meanwhile, doped Mn cations activate the oxidation ability of surrounding Fe atoms through the strong electron transfer between Mn and Fe, making Fe become the main reaction site of NH3 oxidation into NH2 species, and inhibit its excessive oxidation to NH species. This mechanism provides theoretical support for exploring the interaction between binary metal oxides and improving the activity and N2 selectivity of NH3-SCR catalysts at low temperature.