Permanent blockade of in situ-generated acid Brønsted sites of vanadyl pyrophosphate catalysts by pyridine during the partial oxidation of toluene

Abstract

The permanent blockade of in situ-formed Brønsted-acid OH groups and an effective lowering of the catalyst acidity during the partial oxidation of toluene to benzaldehyde is demonstrated by an efficient method using a continuous dosing of pyridine to the feed that leads to drastically increased aldehyde selectivities.

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