A review on alkyl levulinates synthesis from renewable levulinic acid using various modified carbon-based catalysts

Abstract

Alkyl levulinates have significantly attracted the attention of researchers around the world due to their high potential in various applications especially as fuel-blending chemical to improve fuel properties and performance. Alkyl levulinates can be derived from biomass derivative components such as levulinic acid via alcoholysis reaction. Current research progress on the levulinic acid alcoholysis involves the development of effective catalytic synthesis to improve the levulinates yield. This includes the role of catalyst properties and reaction condition applied during the reaction synthesis. In the last few years, a number of catalysts derived from various types of precursors have been studied to synthesize levulinates from levulinic acid. Catalysts from carbonaceous materials offer several advantages such as environmentally friendly, wide availability, high sustainability, and economical, despite the low alkyl levulinates yield obtained upon the utilization of the catalysts for alcoholysis reaction. Thus, the potential of solid acid carbon-based catalyst has been focused in this review due to the increasing number of applications of carbon-based material as catalyst or catalyst support via various modifications. Extensive research on alkyl levulinates synthesis and applications is required to be emphasized. Therefore, the present article describes the wide potential of alkyl levulinates, fundamental research work, progress research, advantages of alkyl levulinates as a fuel blender, and the future direction for reaction synthesis particularly on the improvement of carbon-based catalyst properties and potential emerging technology.