Influences analysis of Sb/Si dopant in TiO2 on NH3-SCR activity and low temperature SO2 resistance of V2O5/TiO2 catalysts.

[Display omitted] • The type of dopant atom changed the physiochemical characters of catalysts discriminately. • Surface chemical properties of catalysts determined their catalytic and anti-poisoning performances. • The support doped catalysts showed the better low temperature SO 2 resistance. • The formation of ammonium bisulfate species is inhibited on Sb/Si doping V 2 O 5 /TiO 2 catalysts surfaces. • The electronic transfer caused by formed surface sulfate species improved SCR activity of V 2 O 5 /Sb-TiO 2. The Sb/Si doped TiO 2 prepared by sol–gel method were used as supports of V 2 O 5 /TiO 2 SCR catalysts in order to improve SCR activity and SO 2 resistance. The type of dopant atoms changed catalyst physiochemical properties discriminatively. Surface chemical properties of catalysts played more important role in their catalytic performance. Simultaneous enhanced surface acidity and redox capacity leaded to the better SCR activity for V 2 O 5 /Sb-TiO 2 compared with other catalysts. The low temperature SO 2 resistance was improved for the support doped catalysts. The special electronic charge migration brought by surface sulfate species for V 2 O 5 /Sb-TiO 2 even elevated its SCR activity during SO 2 resistance test, which was due to the formation of new acid sites and enhancement of redox performance. Even though NO x conversion for V 2 O 5 /Si-TiO 2 decreased, the relative stable efficiency was kept at low temperatures with SO 2. The results proved hetero atom doping in TiO 2 by sol–gel method was a useful method to improve low temperature SO 2 resistance of catalysts. By contrast, Sb is a better choice for the development of support doped V 2 O 5 /TiO 2 SCR catalyst used in a wide temperature range. [ABSTRACT FROM AUTHOR]