MOFs-templated MgO/ZrO₂ enable highly selective glucose-to-fructose conversion. Structural confinement suppresses MgO agglomeration and tunes basicity, achieving 38.4% yield with 90.9% selectivity.

Abstract

High-selectivity glucose isomerization to fructose is essential for the biorefinery industry and fructose syrup production. In this work, a catalyst with tailored basicity was synthesized via the calcination of a MOFs (metal-organic frameworks)-based composite and employed as a chemo-catalyst for glucose isomerization, achieving high fructose selectivity. Characterization results confirmed that the synthesized catalyst was a composite consisting of ZrO2${\rm ZrO}_2$ and MgO, with MgO highly dispersed within the channels of ZrO2${\rm ZrO}_2$. The MOFs templating effect restricted particle size and minimized agglomeration of MgO particles, enhancing the interaction between MgO and ZrO2${\rm ZrO}_2$. This strong interaction effectively modulated the basicity of the catalyst, resulting in the predominance of weak basic sites. As a result, the catalyst demonstrated superior performance in glucose isomerization, achieving a 38.4% fructose yield with 90.9% selectivity at a 10 wt% glucose concentration, outperforming catalysts prepared by conventional methods. However, Mg2+${\rm Mg}^{2+}$ leaching remains a challenge. This work presents a novel approach for synthesizing highly dispersed mixed oxides and provides an effective catalyst for glucose isomerization.