CuZnCoOx multifunctional catalyst for in situ hydrogenation of 5-hydroxymethylfurfural with ethanol as hydrogen carrier

Abstract

Catalytic in situ hydrogenation of 5-hydroxymethylfurfural (5-HMF) to 2,5-dimethylfuran (DMF) has received a great interest in recent years. However, the issue of the consumption of expensive hydrogen donors, such as secondary alcohols, limits its applications. In this work, a ternary CuZnCoOx catalyst, exhibiting a 99% yield of DMF from in situ hydrogenation of 5-HMF with ethanol as economical hydrogen donor, is developed. High resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDS-mapping), X-ray diffraction (XRD) and temperature programmed reduction (TPR) reveal the synergy effect of each components. Reaction mechanism studies unravel the CoOx results in promoting in situ H2 production from ethanol, the zinc oxide accelerates the aldehyde group (CHO) hydrogenation to hydroxymethyl group (CH2OH) and the formation of Cu-Co alloy significantly facilitate the hydrogenation of 5-HMF. Additionally, this ternary CuZnCoOx catalyst exhibits superior recyclability without losing any activity during 6 cycles experiment.