Infrared Characterization of the Hydrocarbon Intermediates In the Oxidation of Toluene and Xylenes Over Vanadia Titania Catalysts

The IR spectra of adsorbed species arising from the interaction of toluene, o-xylene, m-xylene and p-xylene vapours with the surface of a vanadia-titania selective oxidation catalyst are discussed. It is concluded that they are due to benzyl- and methylbenzyl-vanadium species arising from hydrogen abstraction from the hydrocarbon molecule. These species are thought to play a key role in the oxidation mechanism