Dehydration of Glycerol to Acrolein over Hierarchical ZSM-5 Zeolites: Effects of Mesoporosity and Acidity

Selective dehydration of glycerol to value-added acrolein is an interesting catalytic process not only owing to the increasing coproduction of glycerol in the biodiesel production but also due to the emerging perspectives to provide a sustainable route for acrolein production. The use of zeolites in glycerol dehydration is a very promising way with high performance, but these microporous catalysts are often severely constrained by the rapid catalyst deactivation due to coke formation. Although the introduction of hierarchical structure in microporous zeolite crystals is believed to be an effective approach to enhance their activity and lifetime, the relationship between the mesoporosity and catalytic performance is still controversial. In this paper, four kinds of typical hierarchical ZSM-5 catalysts with diverse mesoporosity and similar microporosity/acidity are prepared by the salt-aided seed-induced route. By systematically studying their catalytic performances, the effects of various mesopore types on...