Utilization of guaiacol-based deep eutectic solvent for achieving a sustainable biorefinery

This study proposed a renewable deep eutectic solvent (DES) pretreatment using lignin-derived guaiacol as the hydrogen bond donor. The DES showed excellent biomass fractionation efficiency after the incorporation of trace AlCl3 as the reinforcer, which removed 79.1 % lignin while preserving more than 90 % glucan. The pretreated bamboo exhibited 96.2 % glucan enzymatic hydrolysis yield at only 110 ?. The physicochemical properties of the pretreated solids were comprehensively investigated to explain how the DES fractionation overcame the biomass recalcitrance. The regenerated lignin from the DES pretreatment was also analyzed, which revealed that lignin beta-O-4 bond was significantly cleaved. This guaiacol-based DES could greatly contribute to establish a closed-loop biorefinery sequence with high lignin fractionation efficiency and great solvent recyclability.

Automated summary

This study proposed a renewable deep eutectic solvent (DES) pretreatment using lignin-derived guaiacol as the hydrogen bond donor. The DES showed excellent biomass fractionation efficiency after incorporating trace AlCl3 as the reinforcer, demonstrating the ability to remove lignin while preserving glucan. The physicochemical properties of the pretreated solids were comprehensively investigated, and the regenerated lignin from the DES pretreatment was analyzed, revealing significant cleavage of lignin beta-O-4 bond. This guaiacol-based DES could greatly contribute to establishing a closed-loop biorefinery sequence.