MnO_(x)and Sm–Mn catalysts were prepared with the coprecipitation method,and they showed excellent activities and sulfur resistances for the selective catalytic reduction of NO_(x)by NH_(3)between 50 and 300℃in the ...MnO_(x)and Sm–Mn catalysts were prepared with the coprecipitation method,and they showed excellent activities and sulfur resistances for the selective catalytic reduction of NO_(x)by NH_(3)between 50 and 300℃in the presence of excess oxygen.0.10Sm–Mn catalyst indicated better catalytic activity and sulfur resistance.Additionally,the Sm doping led to multi-aspect impacts on the phases,morphology structures,gas adsorption,reactions process,and specific surface areas.Therefore,it significantly enhances the NO conversion,N_(2)selectivity,and sulfur resistance.Based on various experimental characterization results,the reaction mechanism of catalysts and the effect of SO_(2)on the reaction process about the catalysts were extensively explored.For 0.10Sm–Mn catalyst,manganese sulfate and sulfur ammonium cannot be generated broadly under the influence of SO_(2)and the amount of surface adsorbed oxygen.The Bronsted acid sites strengthen significantly due to the addition of SO_(2),enhancing the sulfur resistance of the 0.10Sm–Mn catalyst.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.52102367)and the Fundamental Research Funds for the Central Universities(WUT,effect of the synthesis method on denitrification performances of the Mn-based spinel catalysts).
文摘MnO_(x)and Sm–Mn catalysts were prepared with the coprecipitation method,and they showed excellent activities and sulfur resistances for the selective catalytic reduction of NO_(x)by NH_(3)between 50 and 300℃in the presence of excess oxygen.0.10Sm–Mn catalyst indicated better catalytic activity and sulfur resistance.Additionally,the Sm doping led to multi-aspect impacts on the phases,morphology structures,gas adsorption,reactions process,and specific surface areas.Therefore,it significantly enhances the NO conversion,N_(2)selectivity,and sulfur resistance.Based on various experimental characterization results,the reaction mechanism of catalysts and the effect of SO_(2)on the reaction process about the catalysts were extensively explored.For 0.10Sm–Mn catalyst,manganese sulfate and sulfur ammonium cannot be generated broadly under the influence of SO_(2)and the amount of surface adsorbed oxygen.The Bronsted acid sites strengthen significantly due to the addition of SO_(2),enhancing the sulfur resistance of the 0.10Sm–Mn catalyst.
