Conversion of Sugars and Biomass to Furans Using Heterogeneous Catalysts in Biphasic Solvent Systems

Within the last decade, interest in using biphasic systems for producing furans from biomass has grown significantly. Biphasic systems continuously extract furans into the organic phase, which prevents degradation reactions and potentially allows for easier separations of the products. Several heterogeneous catalyst types, including zeolites, ion exchange resins, niobium-based, and others, have been used with various organic solvents to increase furan yields from sugar dehydration reactions. In this minireview, we summarized the use of heterogeneous catalysts in biphasic systems for furfural and 5-hydroxymethylfurfural production from the past five years, highlighting trends in chemical and physical properties that effect catalytic activity. Additionally, the selection of an organic solvent for a biphasic system is extremely important and we review and discuss properties of the most commonly used organic solvents.