Low-temperature selective catalytic reduction of NO on MnOx/TiO2 prepared by different methods

Catalysts based on MnOx/TiO2 were prepared by sol-gel, impregnation, and coprecipitation methods for low-temperature selective catalytic reduction (SCR) of NO with NH3. Among the catalysts, the sample prepared by sol-gel method had the best performance on both activity and SO2 resistance. From the results of thermo gravimetric analysis (TGA), X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectrum (XPS), it was known that manganese oxides and titania existed in different phase in the samples prepared by three methods. Strong interaction, large surface area, high concentration of hydroxyl groups, high concentration of amorphous Mn on the surface might be the main reasons for the excellent performance of the catalysts.