High-efficiency fractionation and enzymatic saccharification of poplar wood through biphasic pretreatment with tartaric acid and benzyl alcohol

Biomass pretreatment presents the challenge of simultaneously achieving high-efficiency lignin and hemicellulose removal while preventing lignin condensation and redeposition. To address this challenge, this study introduces a biphasic pretreatment strategy integrating benzyl alcohol (BA) and tartaric acid (TTA) to enhance the selective fractionation of poplar biomass while effectively mitigating lignin polycondensation. Under optimized conditions (160 °C, 40 % BA (v/v), 60 min, and 30 % TTA (w/w)), the pretreatment achieved 98.52 % lignin removal, 97.96 % hemicellulose removal, and 90.76 % cellulose retention. The enzymatic hydrolysis of the cellulose-enriched solid residue yielded an exceptional saccharification rate of 97.00 %, demonstrating the effectiveness of this strategy. Moreover, nuclear magnetic resonance (NMR) analysis revealed that the extracted lignin retained its molecular integrity, highlighting its potential for further valorization. These findings provide crucial insights into optimizing biphasic pretreatment strategies for efficient biomass conversion and advancing high-value lignin applications.