Infrared study of the adsorption of but-1-ene, buta-1,3-diene, furan and maleic anhydride on the surface of anhydrous vanadyl pyrophosphate

Abstract

Brønsted-acidic hydroxy groups on the surface of vanadyl pyrophosphate act as catalytically active sites for the isomerisation of but-1-ene to but-2-enes. Progressive poisoning of the reaction is attributed to the formation of alkyl species, possibly alkoxy groups, on the (VO)₂P₂O₇ surface. Adsorbed alkyl groups also result from buta-1,3-diene adsorption. Furan adsorbs on (VO)₂P₂O₇ through coordinative interactions with Lewis-acidic surface sites. The presence of oxygen promotes the oxidation of furan to maleic anhydride.