Department of Applied Chemical Engineering, Dankook University, Cheonan, Chungnam 330-714, Korea.
Appl Biochem Biotechnol. 2010 May;161(1-8):22-33. doi: 10.1007/s12010-009-8898-z. Epub 2010 Jan 20.
Biological conversion of biomass into fuels and chemicals requires hydrolysis of the polysaccharide fraction into monomeric sugars prior to fermentation. Hydrolysis can be performed enzymatically or with mineral acids. In this study, dilute sulfuric acid was used as a catalyst for the pretreatment of rapeseed straw. The purpose of this study is to optimize the pretreatment process in a 15-mL bomb tube reactor and investigate the effects of the acid concentration, temperature, and reaction time. These parameters influence hemicellulose removal and production of sugars (xylose, glucose, and arabinose) in the hydrolyzate as well as the formation of by-products (furfural, 5-hydroxymethylfurfural, and acetic acid). Statistical analysis was based on a model composition corresponding to a 3(3) orthogonal factorial design and employed the response surface methodology to optimize the pretreatment conditions, aiming to attain maximum xylan, mannan, and galactan (XMG) extraction from hemicellulose of rapeseed straw. The obtained optimum conditions were: H2SO4 concentration of 1.76% and temperature of 152.6 degrees C with a reaction time of 21 min. Under these optimal conditions, 85.5% of the total sugar was recovered after acid hydrolysis (78.9% XMG and 6.6% glucan). The hydrolyzate contained 1.60 g/L glucose, 0.61 g/L arabinose, 10.49 g/L xylose, mannose, and galactose, 0.39 g/L cellobiose, 0.94 g/L fructose, 0.02 g/L 1,6-anhydro-glucose, 1.17 g/L formic acid, 2.94 g/L acetic acid, 0.04 g/L levulinic acid, 0.04 g/L 5-hydroxymethylfurfural, and 0.98 g/L furfural.
生物质转化为燃料和化学品需要在发酵前将多糖部分水解为单体糖。水解可以通过酶法或矿物酸法进行。在这项研究中，稀硫酸被用作油菜秸秆预处理的催化剂。本研究的目的是优化 15-mL 炸弹管反应器中的预处理工艺，并研究酸浓度、温度和反应时间的影响。这些参数影响半纤维素的去除和水解产物（木糖、葡萄糖和阿拉伯糖）的产量，以及副产物（糠醛、5-羟甲基糠醛和乙酸）的形成。统计分析基于与 3(3)正交因子设计相对应的模型组成，采用响应面法优化预处理条件，旨在从油菜秸秆半纤维素中获得最大的木聚糖、甘露聚糖和半乳糖（XMG）提取。得到的最佳条件为：H2SO4浓度为 1.76%，温度为 152.6°C，反应时间为 21min。在这些最佳条件下，酸水解后回收了 85.5%的总糖（78.9%的 XMG 和 6.6%的葡聚糖）。水解产物中含有 1.60g/L 葡萄糖、0.61g/L 阿拉伯糖、10.49g/L 木糖、甘露糖和半乳糖、0.39g/L 纤维二糖、0.94g/L 果糖、0.02g/L 1,6-脱水葡萄糖、0.39g/L 甲酸、2.94g/L 乙酸、0.04g/L 乙酰丙酸、0.04g/L 5-羟甲基糠醛和 0.98g/L 糠醛。
