多元醇基三元DES预处理提高玉米秸秆酶解性能研究

Study on Enzymatic Hydrolysis Improvement of Corn Stalk with Polyol-based Ternary DES Pretreatment

关键词:  玉米秸秆  低共熔溶剂  预处理  酶解性能  多元醇

Key Words:corn stalk  deep eutectic solvent  pretreatment  enzymatic hydrolysis  polyol

摘要:探究了新型多元醇基低共熔溶剂（DES）预处理对玉米秸秆组分、表面形貌、纤维素聚合度（DP）和酶解效率的影响规律。结果表明，多元醇基DES预处理可高效脱除玉米秸秆的半纤维素和酸不溶木质素（AIL），并有效保留纤维素，多元醇碳链长度与预处理性能不存在正相关关系；氯化胆碱/1,4-丁二醇/4-羟基苯磺酸为最佳多元醇基DES体系，脱除了近100%的半纤维素和98%的AIL，纤维素保留率达84%，DP降至894；预处理玉米秸秆表面粗糙多孔，未发现沉积的木质素和假木质素颗粒；此时酶解效率高达94.80%，是玉米秸秆原料的5.9倍。综上所述，多元醇基DES预处理通过降低纤维素DP，脱除半纤维素和AIL，同时抑制木质素重新沉积，提高玉米秸秆表面粗糙性，可以极大提升酶解性能。

Abstract:Effects of novel polyol-based deep eutectic solvent （DES） pretreatment on corn stalk components， surface morphology， polymerization degree （DP） of cellulose， and enzymatic efficiency were investigated. The results showed that polyol-based DES pretreatment could efficiently remove hemicellulose and acid insoluble lignin （AIL） from corn stalk and retain cellulose， but there was no positive correlation between the carbon chain length of polyol and pretreatment performance. Choline chloride/1，4-butanediol/4-hydroxy benzenesulfonic acid was the optimum polyol-based DES system， removing nearly 100% hemicellulose and 98% AIL， but saving 84% cellulose and DP=894. The surface of pretreated corn stalk was rough， porous， and no deposited lignin and pseudo-lignin particles. The corresponding enzymatic efficiency was as high as 94.80%， which was 5.9 times higher than that of raw corn stalk. In summary， the polyol-based DES pretreatment could greatly enhance the enzymatic performance by reducing cellulose DP， removing hemicellulose and AIL， and simultaneously inhibiting lignin redeposition and improving the surface roughness of corn stalk.