Production of levulinic acid from lignocellulosic biomass with a recyclable aromatic acid and its kinetic study

Abstract

Levulinic acid (LA), a renewable and valuable platform chemical from lignocellulosic biomass, has exhibited major potential in the production of biomaterials and biofuels. This study reports the production of LA from lignocellulose using a recyclable aromatic acid, toluene sulfonic acid (p-TsOH), and its reaction kinetics were investigated. The adoption of p-TsOH, which has a special hydrophobic and hydrophilic structure, dramatically improved the yield of LA to a competitive level (57.9±4.1%) at the optimum conditions (reaction temperature = 162 °C, catalyst concentration = 0.95 mol/L, and reaction time = 64 min). Meanwhile, the kinetics involving the simultaneous conversion of both glucan (the cellulose component) and mannan (the hemicellulose component) to LA were examined. The results indicated that the activation energy values in the reaction kinetics were lower than those in previous studies that used H2SO4 as a catalyst. Consequently, the maximum yield of LA was easily obtained at a lower temperature (170 °C). The results of this study are important for process modelling applications and the production of LA from lignocellulosic materials.