酸/碱性低共熔溶剂预处理对轻木物化性质及酶水解影响

Effects of Pretreatment with Acidic/Alkaline Deep Eutectic Solvents on Physical and Chemical Properties and Cellulose Enzymatic Hydrolysis of Balsa Wood

采用酸/碱性低共熔溶剂(DES)在110℃和5 h下预处理轻木原料,分析了预处理前后轻木的化学组成、表面形貌、结构变化和酶水解性能。结果表明,3种酸/碱性DES预处理均可有效解构轻木原料。酸性DES可去除几乎所有的半纤维素和部分木质素,且酸性较强的氯化铝六水合物/丙三醇体系处理导致部分纤维素降解。碱性氯化胆碱/乙醇胺体系预处理后木质素大量去除,残留物中保留大量碳水化合物。预处理可显著增效纤维素酶水解,葡萄糖得率由原料的16.5%提升至52.6%~60.7%。DES经循环使用3次后纤维素酶解效率仍可达原料的2.5倍以上。

Balsa wood was subjected to acidic/alkaline deep eutectic solvent(DES)pretreatment at 110℃for 5 h,and the chemical composition,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 enhanced 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.