汽爆酸碱耦合解聚玉米秸秆分子结构的研究  

Study on the Molecular Structure of Corn Stalk after Depolymerization with Steam Explosion Coupled with Acid and Alkali

作　　者：孙永刚[1,2] 马玉龙[1,2] 麻晓霞[2] 常璇[2] 惠兴育[2] 孙瑞珠[2] 

机构地区：[1]宁夏大学能源化工国家重点实验室培育基地,银川750021 [2]宁夏大学化学化工学院,银川750021

出　　处：《中国粮油学报》2013年第7期29-35,共7页Journal of the Chinese Cereals and Oils Association

基　　金：国家自然科学基金(21266023);宁夏大学大学生科技创新与人文社会科学研究项目(12HGG14)

摘　　要：以玉米秸秆为研究对象,采用蒸汽爆破+5%H2SO4和蒸汽爆破+5%NaOH的耦合方法对其结构进行解聚处理,并对解聚前后秸秆的结构、化学组成、热稳定性能进行分析和表征。结果表明:与未处理前相比,经蒸汽爆破+碱解聚处理后,秸秆中大部分半纤维素被脱除,半纤维素由29.10%最低可降至4.61%,木质素由38.12%最低可降至10.74%。经蒸汽爆破酸耦合和蒸汽爆破碱耦合解聚处理后,纤维素含量由31.54%分别提高到65.16%和80.41%,秸秆最大失重率为81.86%和89.31%,最低吸热量为87.48 J/g和114.79 J/g,降解温度达到350℃,热稳定性能增加,表面结构疏松,出现小孔和裂缝。说明蒸汽爆破酸耦合和蒸汽爆破碱耦合解聚方法对玉米秸秆分子结构有一定的解聚效果。但就脱除半纤维素效果而言,蒸汽爆破碱耦合法优于蒸汽爆破酸耦合法。Corn stalk, as the research objective, was depolymerized using either steam explosion coupled with 5% H2SO4 or steam explosion coupled with 5% NaOH, and then the structure, chemical composition and thermal stability property of corn stalk before and after depolymerization were analyzed and characterized. The results showed that treatment with steam explosion and alkali depolymerization removed most of hemicellulose in corn stalk as compared to those of the untreated stalk, and the hemicellulose compositions were decreased from 29.10% to the mini- mum 4.61%, the lignins from 38.12% to the minimum 10.74%. While the celluloses were increased from 31.54% to 65.16% and 80.41%, the maximum weight loss rate of stalk of 81.86% and 89.31% , the lowest absorbed heat of 87.48 J/g and 114.79 J/g respectively after depolymerization with steam explosion coupled with acid and base respectively. The surface morphology became loose, and holes and cracks appeared after depolymerization of corn stalk ; the thermal stability increased and the degradation temperature reached over 350 ℃. These results suggest that steam explosion coupled with acid and alkali has a certain depolymerization effect on the molecular structure of corn stalk, but in terms of removal of hemicellulose, the depolymerization effect of steam explosion coupled with alkali is better than that of steam explosion coupled with acid.

关 键 词：蒸汽爆破 酸碱 解聚 玉米秸秆 

分 类 号：TQ353.14[化学工程]