Levulinic Acid Is a Key Strategic Chemical from Biomass

Levulinic acid (LA) is one of the top twelve chemicals listed by the US Department of Energy that can be derived from biomass. It serves as a building block and platform chemical for producing a variety of chemicals, fuels and materials which are currently produced in fossil based refineries. LA is a key strategic chemical, as fuel grade chemicals and plastic substitutes can be produced by its catalytic conversion. LA derivatisation to various product streams, such as alkyl levulinates via esterification, gamma-valerolactone via hydrogenation and N-substituted pyrrolidones via reductive amination and many other transformations of commercial utility are possible owing to the two oxygen functionalities, namely, carbonyl and carboxyl groups, present within the same substrate. Various biomass feedstock, such as agricultural wastes, marine macroalgae, and fresh water microalgae were successfully converted to LA in high yields. Finding a substitute to mineral acid catalysts for the conversion of biomass to LA is a challenge. The use of an ultrasound technique facilitated the production of promising nano-solid acid catalysts including Ga salt of molybophosphoric acid and Ga deposited mordenite zeolite, with optimum amounts of Lewis and Bronsted acidities needed for the conversion of glucose to LA in high yields, being 56 and 59.9 wt.% respectively. Microwave irradiation technology was successfully utilized for the accelerated production of LA (53 wt.%) from glucose in a short duration of 6 min, making use of the unique synergistic catalytic activity of ZnBr2 and HCl.

Automated summary

Levulinic acid (LA) is a biomass-derived chemical listed by the US Department of Energy, which can be used as a building block for producing various chemicals, fuels, and materials. LA has the potential to replace fossil-based refineries in the production of fuel-grade chemicals and plastic substitutes. LA can be derivatized to different products through various reactions. Various biomass feedstocks have been successfully converted to LA with high yields. The use of ultrasound and microwave technologies has shown promising results in the production of LA.