Synergistic effects of peracetic acid and oxalic acid on structural transformation of eucalyptus and its conversion

Biomass pretreatment solvent plays an important role in the utilization of lignocellulosic feedstocks . In this study, the synergistic effects of peracetic acid and oxalic acid (PAO) were investigated as a pretreatment solvent for maximizing cellulose conversion as well as recovering biologically transformable lignin. The PAO pretreatment with 4.5% oxalic acid and 2.0% peracetic acid effectively fractionated lignin (85.4%) under a mild temperature (140 °C) and resulted in a high glucose release (758 mg/g biomass) from the pretreated eucalyptus . Also, the PAO pretreatment could fractionate and deconstruct lignin to low molecular weight (1231 g/mol) aromatics with 5.8% of β-O-4 linkages and a relatively uniform molecular weight distribution (PDI 1.3). The pretreatment using PAA and OA enhanced not only the hydrolysis of cellulose but also the recovery of biologically transformable lignin as a value-added coproduct for a successful biorefinery approach.