研究了极低酸水解对稻壳转化乙酰丙酸和纤维结构的影响.以0.1%的硫酸为催化剂,考察了稻壳水解生成乙酰丙酸的规律.结果显示:适宜的液固比为32:1(mL:g),温度240℃,水解时间30 min.在此条件下,原料纤维素和半纤维素的总转化率为12.81%.采用扫描电镜、X射线衍射仪和红外光谱对稻壳残渣进行表征,结果表明经水解后的稻壳结构发生明显变化,结晶度下降,纤维素和半纤维素被水解.在此基础上,提出了极低酸水解稻壳的综合水解模型.%The effects of extremely-low-concentration acid hydrolysis on levulinic acid production from rice husk and cellulosic structure were investigated. Using dilute sulfuric acid with mess concentration 0.1％ as catalyst, the levulinic acid production from rice husk was studied. The results show that the optimal ratio of liquid to solid is 32:1 ( mL: g }, temperature is 24O ℃, and hydrolysis time is 30 min. Under these conditions, 12.81％ of the total mass conversion yield of cellulose and hemicellulose can be obtained. The cellulosic structure was characterized by methods of scanning electron microscopy, X-rays diffraction and infrared. The results show that though hydrolysis the cellulosic structure was destroyed remarkably. The crystallinity decreased. and cellulose and hemicellulose were also hydrolyzed. On this basis, a comprehensive hydrolysis model of ace husk was proposed finally.
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