化工学报2012，Vol.63Issue(2)：599-605,7.DOI:10.3969/j.issn.0438-1157.2012.02.037
高温液态水中甜高梁渣半纤维素水解及其机理
Hydrolysis of sweet sorghum bagasse hemiceilulose with liquid hot water and its mechanism
摘要
Abstract
Sweet sorghum bagasse (SSB) was hydrolyzed with liquid hot water in a flow-through reactor with the objective of achieving complete saccharification of hemicellulose of SSB and understanding the hydrolysis mechanism. The effect of reaction temperature (155-235°C) and flow rate (5-30 ml · Min-1) on the concentration of xylose, glucose, arabinose, their total sugars and their degradation products (furfural, 5-HMF, acetic acid, glucuronic acid, formic acid and glycolic acid) in the liquid fractions was investigated. The experimental results indicated that xylose was more sensitive to temperature and flow rate than arabinose and glucose. The concentration of total xylose including xylose monomer and xylose oligomer dropped dramatically when temperature was higher than 195°C. A lower flow rate (5 ml · Min-1) resulted in a higher furfural yield due to longer residence time for xylose in the reactor. In contrast, a higher flow rate (30 ml · Min-1) would reduce the thickness of stagnant fluid layer surrounding the solid particles and lower resistance to penetration of water into the solids for hydrolysis and diffusion of oligomers into solution. It was hypothesized that the major xylan in SSB hemicellulose was Oacetyl-4-O methyl-glucuronoarabinoxylan. Xylose, arabinose, glucose and their oligosaccharides could be considered as the primary products. Glucuronic acid and acetic acid were produced from the decomposition of glucuronic and O-acetyl groups in the branched chain of hemicellulose. Furfural and 5-hydroxymethyl-2-furaldehyde (5-HMF) were the direct degradation products of sugars. Moreover, glucuronic acid would befurther oxidatively degraded into glycolic acid. Low molecular weight organic acids, such as formic acid were the further degradation products.关键词
高温液态水/甜高粱渣/水解/半纤维素/机理Key words
liquid hot water/ sweet sorghum bagasse/ hydrolysis/ hemicellulose/ mechanism分类
化学化工引用本文复制引用
余强,庄新姝,袁振宏,王闻,亓伟,王琼,谭雪松..高温液态水中甜高梁渣半纤维素水解及其机理[J].化工学报,2012,63(2):599-605,7.基金项目
国家科技支撑计划项目(2011BAD22B01) （2011BAD22B01）
国家高技术研究发展计划项目(2010AA101606) （2010AA101606）
中国科学院知识创新工程项目(KSCX2-YW-C-063,KSCX1-YW-11-A3). （KSCX2-YW-C-063,KSCX1-YW-11-A3）
