Effects of Pretreatment with Acidic/Alkaline Deep Eutectic Solvents on Physical and Chemical Properties and Cellulose Enzymatic Hydrolysis of Balsa Wood
Balsa wood was subjected to acidic/alkaline deep eutectic solvent(DES)pretreatment at 110℃for 5 h,and the chemical compo-sition,surface morphology,structural variation,and enzymatic hydrolysis performance of the balsa wood before and after pretreatment were analyzed.The results showed that all three types of acidic/alkaline DES pretreatments effectively deconstructed the balsa wood raw material.The acidic DES removed nearly all hemicelluloses and a portion of lignin,with the stronger acidic treatment using acidic aluminum chloride hexahydrate/propanetriol system resulting in partial cellulose degradation.The alkaline choline chloride/ethanolamine system pretreatment led to substantial removal of lignin while preserving a significant amount of carbohydrates in the residue.The pretreatment significantly en-hanced cellulase hydrolysis,increasing the glucose yield from 16.5%in the raw material to 52.6%~60.7%.Even after being recycled three times,the cellulose hydrolysis rate of DES remained more than 2.5 times higher than that of the raw material.