School of Energy & Environment, Southeast University, Key Laboratoryof Energy Thermal Conversion and Control of Ministry of Education, Nanjing 211189, China
To enhance the resistance of vanadium tungsten titanium (V2O5-WO3-TiO2) catalysts to alkaline earth metal poisoning and broaden the reaction temperature window,a series of Ce(SO4)2-V2O5-WO3-TiO2 (referred to as Ce-V-W-Ti) catalysts are prepared via an equal volume impregnation method.The influence of Ce(SO4)2 addition amount on the denitrification performance of the catalysts is studied,and the catalysts are characterized by means of N2 adsorption-desorption,XRD,XPS,and NH3-TPD.Density functional theory calculation is used to explore further the mechanism of the catalysts’ resistance to alkaline earth metal poisoning.Results show that the doping of Ce(SO4)2 increases the proportion of chemically adsorbed oxygen on the surface,promotes the redox process between V4+/V5+ and Ce3+/Ce4+,and increases weak acid and strong acid sites on the surface of catalysts.Ce1V1W8/90Ti has the best modification effect,and its denitrification performance at 200-400℃ is significantly better than that of V1W8/91Ti.Under the reaction conditions of 300℃ and n(CaO)/n(V2O5)=3,NOx removal rate increases from 46.07% to 63.71%.In the atmosphere containing SO2 at 350℃,NOx removal rate always remains above 97%.
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