Efficient and Scalable Production of Alkyl Levulinates from Cellulose-Derived Levulinic Acid Using Heteropolyacid Catalysts

This work reports a straightforward and scalable synthesis of a series of alkyl levulinates from cellulose-derived levulinic acid and alkyl alcohols using commercially available heteropolyacid catalysts under homegenous conditions. The reaction was optimized on parameters such as temperature, molar ratio of reagents, type and loading of catalyst. The solvent-free reactions afforded alkyl levulinates in high isolated yields (>85%) using only slight excess of alcohols and 10 wt% of catalyst at 120 degrees C in 6 h. Further, the catalysts were successfully recycled for three consecutive cycles without significant loss in activity.