Highly efficient dehydration of polyols: In-situ Brønsted acid from boron phosphate catalyst

Abstract

Dehydroxylation of biomass-based platform molecules is critical for obtaining building blocks for use in the chemical industry. Acid catalytic dehydration has provided a feasible route. However, simultaneously pursuing high product-selective and ultra-stable catalysts for the dehydroxylation of polyols remains an open challenge. In this study, a strategy for in-situ Brønsted acid sites (BAS) with chemo-adsorption selectivity is proposed. The construction of defect sites B[3] and P[4] species has been proved to be a prerequisite for the dynamic acid site formation at hydrothermal conditions. The BPO4 catalyst with in-situ BAS can achieve the high selectivity of acrolein (∼80%) and robust stability of catalyst (over 425 h) using glycerol dehydration as a model reaction. In addition, in-situ BAS is highly selective for secondary hydroxyl groups and has been extended to other substrate applications. This catalytic strategy provides a green, efficient, and economical approach for converting biomass-derived polyols to high-value-added chemicals.