In Situ FT-IR Mechanistic Investigations of the Zeolite Catalyzed Methylation of Benzene with Methanol: H-ZSM-5 versus H-beta

Abstract

The methylation of aromatics is a reaction step that occurs in several petrochemical processes. Here, we have investigated the methylation of benzene by methanol over H-ZSM-5 and H-beta catalysts by conducting kinetic measurements and in situ FT-IR spectroscopy at comparable reaction conditions. A lower rate of methylation per Bronsted acid site is seen for H-beta, and this is linked to the formation of fairly persistent cationic species, as observed with FT-IR.