The selective catalytic reduction (SCR) of NO with C3H6 was studied over th
ree noble-metal-based catalysts: 2% Pt/gamma-Al2O3, 2% Rh/gamma-Al2O3 and 1
.5% Rh/TiO2(4% WO3). The SO2 effect on the catalyst activity was examined u
sing sulfated samples of the above catalysts and SO2-containing feeds. Temp
erature-programmed desorption and oxidation studies were carried out to exa
mine the adsorption characteristics of NO and C3H6, respectively, in the ab
sence or the presence of SO2. The adsorption data were linked to variations
in the NO reduction rates over fresh and sulfated samples. Modification of
the support surface as a result of the SO2 presence affects the NO and pro
pene sorption characteristics, the NO oxidation and the propene consumption
rates.