(540c) Lignin-Derived Deep Eutectic Solvents Pretreatment of Herbal Residues to Enhance Enzymatic Digestibility of Cellulose

A lignin-derived eutectic solvent was synthesized from choline chloride(ChCl) and p-coumaric acid(PCA). The results showed that after pretreatment with lignin-derived DES, the dense cellulose-hemicellulose-lignin structure of herb residue of cortex albiziae(HRCA) was effectively breakn down and this facilitated subsequent enzymatic hydrolysis. The optimum pretreatment condition was ChCl /PCA molar ratio of 1:1, 160°C-5 h, and solid-liquid ratio of 1:10. Compared with the untreated HRCA, 72h-enzymatic digestibility increased from 48.08% to 84.62%. When taking a water-DES pretreatment, the 72h digestibility level of the residue reached 99.36%. Moreover, it was found that the performance of DES pretreatment was closely related to the type of raw materials. Furthermore, the recycling and reusability of this novel DES were evaluated as well. Thus, synthesis and utilization of green, environment-friendly and recyclable lignin-derived DES would opened up a new way of lignin utilization and it has great potential in biomass refining.