"‘Insitu’' DRIFTS study of the SCR reaction of NO with ammonia over a high loading (15% weight) vanadia–titania catalyst

Abstract

The Selective Catalytic Reduction (SCR) of NO with ammonia over a high loading vanadia–titania catalyst has been studied by "‘insitu’' Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). In the reaction steady state a linear relationship between the NO conversion and the area of the 2ν(VO) IR band is found. This result suggests that VO species are the active sites in the SCR reaction over vanadia–titania catalysts. On the other hand, although NH₄⁺ is the only adsorbed NH₃ species detected in reaction conditions, the catalyst activity does not correlate with their surface concentration.