不同水热预处理方法对水稻秸秆组成结构及酶解特性的影响  

EFFECT OF VARIOUS HYDROTHERMAL PRETREATMENTS ON COMPOSITION,STRUCTURE AND ENZYMATIC HYDROLYSIS OF RICE STRAW

作　　者：王泓 晏文菁 杨芸芸 马一可 李东妮 李俊贤 华煜 戴晓虎[1] WANG Hong;YAN Wenjing;YANG Yunyun;MA Yike;LI Dongni;LI Junxian;HUA Yu;DAI Xiaohu(State Key Laboratory of Pollution Control and Resource Reuse,College of Environmental Science and Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学环境科学与工程学院污染控制与资源化研究国家重点实验室,上海200092

出　　处：《环境工程》2024年第9期285-291,共7页Environmental Engineering

基　　金：国家重点研发计划(2020YFC1908702);国家自然科学基金项目(52200172);中国博士后科学基金(2022M712404)。

摘　　要：为探明不同水热预处理方法对秸秆结构特征、化学组成和酶解特性的影响及其机制,采用了单独水热、KOH、CH_(3)COOH、HCl、FeCl_(2)5种水热条件对水稻秸秆进行预处理,从物料损失、化学组分、比表面积、孔隙结构、化学结构、表面粗糙度、粒径分布及酶解后糖浓度进行分析,阐明了不同预处理方法对秸秆组成结构及酶解特性的影响机制。结果表明:碱热预处理能通过酯键的断裂从而有效去除秸秆中的木质素,木质素回收率低至46.2%;而木质素的溶出造成了孔道坍塌,相对结晶度显著增加(38.9%),孔径和比表面积减小至9.24 nm和2.62 m^(2)/g。酸处理均能促进半纤维素的溶解,使得秸秆中形成了更多的小孔和微孔。碱热预处理后,秸秆的粒径由0.334 mm降至0.141 mm,分形维数由1.92减至1.71,疏松的结构促进了酶解反应效率,总糖浓度达到39.9 g/L,且葡萄糖和木糖占比较大,而HCl组预处理后的葡萄糖含量最高。To investigate the effects and mechanisms of various hydrothermal pretreatment on the physicochemical structure,chemical composition and enzymatic hydrolysis of rice straw,four pretreatment methods,pure hydrothermal,KOH,CH_(3)COOH,HCl and FeCl_(2),were all used to treat rice straw.The material loss,chemical composition,specific surface area,pore structure,chemical structure,roughness,particle size,and changes in sugar concentration after enzymatic hydrolysis were explored.The results showed that alkaline-thermal pretreatment could effectively remove the lignin from the straw by breaking the ester bond,and the lignin recovery rate decreased to 46.2%.Furthermore,the dissolution of the lignin caused a severe collapse of the internal structure of the straw.The relative crystallinity increased significantly by 38.9%,and the pore size decreased to 9.24 mm,while the surface area decreased to 2.62 m^(2)/g.Acid treatment had a greater impact on the dissolution of hemicellulose,leading to the formation of more small pores and micropores in the straw.After alkaline-thermal pretreatment,the straw particle size was reduced from 0.334 mm to 0.141 mm,and the fractal dimension decreased from 1.92 to 1.71.The loose structure improved the efficiency of the enzymatic hydrolysis reaction.Total sugar concentration reached 39.9 g/L,mainly consisting of glucose and xylose.The highest glucose content was found in the pretreated HCl group.

关 键 词：水稻秸秆 水热预处理 化学组分 木质纤维素 酶解 

分 类 号：X71[环境科学与工程—环境工程]