Ce-Doped V2O5-WO3/TiO2 with Low Vanadium Loadings as SCR Catalysts and the Resistance of H2O and SO2

The promoting effect of Ce on V-W/Ti catalyst for selective catalytic reduction (SCR) of NO x by NH 3 was studied. Compared with the original V-W/Ti samples, addition of Ce contributed better NH 3 -SCR performance. The H 2 O and SO 2 resistance of Ce modified V-W/Ti catalyst was improved by the different impregnation sequence of Ce. The catalysts were characterized by NH 3 -temperature programmed desorption (NH 3 -TPD), X-ray photoelectron spectroscopy (XPS), and H 2 -temperature programmed reduction (H 2 -TPR) techniques. The results showed that the impregnation sequence of W and Ce influenced the NH 3 adsorption capacity of the catalysts. In comparison to 0.2V-5Ce-5W/Ti and 0.2V-(5Ce5W)/Ti, 0.2V-5W-5Ce/Ti catalyst contributed better H 2 O and SO 2 resistance, with the highest Ce 3+ /(Ce 4+  + Ce 3+ ) value of 36.6%. Besides, a catalytic mechanism of SCR reactions over Ce-doped V-W/Ti catalysts was proposed. Graphic