Reaction of NO and NO2 with NH3 over V2O5/AC Catalyst

Temperature-programmed desorption, on-line mass spectroscopy, and in situ diffuse reflectance infrared Fourier transform spectroscopy were preformed to study selective catalytic reduction (SCR) of NO and NO2 with NH3 over V2O5 and activated carbon (AC)-supported V2O5 (V2O5/AC). The results show that both protonated (NH4+) and molecularly coordinated (NH3) ammonia species form on the V2O5 surface and V=O bond is the primary active site. Both NO2 and NO can react with the adsorbed ammonia in the absence of oxygen, but the activity of NO2 is superior to that of NO. On the V2O5/AC surface, NO2 Still can react with the adsorbed NH3 species to form N-2, but NO shows little activity unless oxygen is present. SCR of NO on V2O5/AC proceeds through oxidation of NO to NO2 by oxygen on the AC surface followed by reaction of NO2 with NH3 Species adsorbed and activated on the V2O5 surface.