Separation and purification of 5-hydroxymethylfurfural by metal‒organic frameworks

Abstract

5-Hydroxymethylfurfural (HMF) is an important sugar-based platform chemical that can be produced from fructose by acid-catalyzed dehydration. However, the efficient removal of by-products formic acid (FA), levulinic acid (LA) and residual fructose to obtain high purity HMF remains a challenge, especially the separation of LA and HMF. Herein, by introducing coordination interaction, we effectively separated HMF from impurities. MOF-808 selectively adsorbed the impurity components with high adsorption capacity and selectivity factor for Fru (238 mg/gads, 43.8), FA (174 mg/gads, 53.5), and LA (325 mg/gads, 43.8). Moreover, the adsorption kinetic constants for MOF-808 on FA and LA could reach remarkably high values of 58.0 h-1 and 25.9 h-1, respectively. The efficient adsorption separation performance of MOF-808 is attributed to its abundant unsaturated paired sites and hard Lewis acidity. Additionally, in practical column separation, MOF-808 showed outstanding separation performance and cycling stability. This study indicates coordination interactions are effective for the separation and purification of HMF.