A mild biomass pretreatment process with efficiency and specificity in co-solvent of γ-valerolactone and aqueous p-toluenesulfonic acid

Efficient depolymerization of lignocellulosic biomass into platform chemicals is of great importance to bring the comprehensive bio-refinery concept into industrial reality. Herein, we reported an environmentally benign pretreatment process for full components utilization of moso bamboo in co-solvent of γ-valerolactone (GVL) and aqueous solution of p-toluenesulfonic acid (TsOH aq). Notably, over 98 wt% of lignin and hemicelluloses could be simultaneously degraded into oligomeric phenols and pentose under the mild condition of 130 °C for 60 min with GVL/TsOH aq volume ratio of 4/1, following with 91.5 wt% of cellulose retained which was then enzymatic hydrolyzed into 773.2 mg/g glucose. All of the obtained platform chemicals could be easily separated and purified, which significantly facilitate the excellent retrieve of the co– solvent. Moreover, the synergistic effect between GVL and TsOH on efficiency and specificity was proposed by control group experiment and verified by molecular dynamics simulation and quantum chemical calculation. This study provides a facile pretreatment and direct conversion strategy for biorefinery process of lignocellulosic biomass in novel GVL/TsOH aq co-solvent.