Glucose Isomerization to Fructose Catalyzed by MgZr Mixed Oxides in Aqueous Solution

Abstract

The catalytic isomerization of glucose to fructose plays a pivotal role in the application of biomass as a feedstock for chemicals. Herein, we propose a facile solid-state-grinding strategy to construct ZrO2/MgO mixed oxides, which offered an excellent fructose yield of over 34.55% and a high selectivity of 80.52% (80 °C, 2 h). The co-mingling of amphiphilic ZrO2 with MgO improved the unfavorable moderate/strongly basic site distribution on MgO, which can prohibit the side reactions during the reaction and enhance the fructose selectivity. Based on the catalyst characterizations, MgO was deposited on the ZrO2 surface by plugging the pores, and the addition of ZrO2 lessened the quantity of strongly basic sites of MgO. Additionally, the presence of ZrO2 largely enhanced the catalyst stability in comparison with pure MgO by recycling experiments.