Levulinic acid production integrated into a sugarcane bagasse based biorefinery using thermal-enzymatic pretreatment

Levulinic acid (LA) is a promising platform chemical that can be produced from C6-sugars of lignocellulose. However, direct conversion of lignocellulose leads to the predefined by-products furfural and a solid residue, composed of lignin and humins. Enabling independent conversion of the major biomass components would increase the flexibility in terms of the products of a biorefinery. Therefore, this work focuses on integrating LA production into a biorefinery, which fractionates the biomass with a thermal -enzymatic treatment using hot water and enzymes only. Besides a glucose solution, used for LA production, a hemicellulose rich hydrolysate and solvent free lignin were recovered. The yields for the C6-fractions after thermal and enzymatic treatment were 95.8 mol% and 62.1 mol%, respectively. The influence of temperature (160-200 C-circle), residence time (3-90 min) and acid concentration (0.25-1 M) on LA synthesis, following thermal -enzymatic treatment was investigated by statistical methods, achieving a maximum LA yield of 67.7 mol%. (C) 2017 Elsevier B.V. All rights reserved.