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

关键词:  轻木  低共熔溶剂  预处理  酶解  循环使用

Key Words:balsa wood  deep eutectic solvent  pretreatment  enzymatic hydrolysis  recycling

摘要: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。

Abstract: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.