Resistance to SO2 poisoning of V2O5/TiO2-PILC catalyst for the selective catalytic reduction of NO by NH3

Abstract

A titania pillared interlayered clay (Ti-PILC) supported vanadia catalyst (V2O5/TiO2-PILC) was prepared by wet impregnation for the selective catalytic reduction (SCR) of NO with ammonia. Compared to the traditional V2O5/TiO2 and V2O5-MoO3/TiO2 catalysts, the V2O5/TiO2-PILC catalyst exhibited a higher activity and better SO2 and H2O resistance in the NH3-SCR reaction. Characterization using TPD, in situ DRIFT and XPS showed that surface sulfate and/or sulfite species and ionic SO42− species were formed on the catalyst in the presence of SO2. The ionic SO42− species on the catalyst surface was one reason for deactivation of the catalyst in SCR. The formation of the ionic SO42− species was correlated with the amount of surface adsorbed oxygen species. Less adsorbed oxygen species gave less ionic SO42− species on the catalyst.