Investigation of the transformations of chlorobenzene at the surface of a vanadium oxide catalyst by IR spectroscopic and thermal desorption methods
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In the present work an IR spectroscopic and thermodesorption investigation of the surface compounds formed by chlorobenzene on a vanadium oxide catalyst was undertaken. It was established that in the initial period of adsorption chlorobenzene forms a weakly bonded π complex with the surface of the catalyst. With subsequent increase in temperature a compound firmly bound to the surface of the catalyst appears. It is most likely that this complex is a σ complex formed through a bond between the reagent molecule and an electrophilic center on the surface. On the basis of the results from the IR-spectroscopic investigations and thermal desorption a mechanism involving intermediate surface compounds detected by IR spectroscopy is proposed for the catalytic oxidation of chlorobenzene.
KeywordsOxide Spectroscopy Vanadium Initial Period Oxide Catalyst
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