玉米秸秆稀酸水解糖化法影响因子的研究

Influencing factors in saccharification of corn stover by dilute sulfuric acid hydrolyzing method

该文通过分析水解还原糖成分,研究了温度、时间、稀酸浓度、固形物含量对水解效率的影响;并结合残渣组分分析研究了稀酸水解过程中纤维素、半纤维素降解的规律。研究表明:在试验条件下玉米秸秆的水解主要以半纤维素为主,随着温度、稀酸浓度和水解时间的增加,纤维素的水解逐渐增强。当水解温度超过100℃后,水解得糖率迅速增加,超过110℃,纤维素开始水解;玉米秸秆的水解在前40min就基本完成,过长的水解时间对水解效率的提高意义不大;水解的酸浓度应控制在1.5%左右;玉米秸秆在低固含物的条件下,水解效率相对较高。方差分析结果显示:温度、酸浓度对水解效率的影响最大,温度和固含物的影响次之,粒径的影响不显著;温度和酸浓度、温度和时间的交互作用对试验结果有影响显著。根据方差分析,最佳水解条件A3B2C3D1E1:温度125℃、时间80min、稀酸浓度1.5%、固形物含量7.5%,在该条件下水解还原糖得率为32.71%。

Different factors that influence hydrolysis rate of corn stover by dilute sulfuric acid hydrolyzing method were studied, including hydrolyzing time, temperature, concentration of sulfuric acid and solid content. The experimental results show that the majority hydrolyzed part of corn stover was hemi-cellulose. The hydrolysis of cellulose needs a longer time, higher temperature and higher sulfuric acid concentration. The influences of temperature, hydrolyzing time, concentration of the dilute sulfuric acid and the solid content in hydrolyzing process were very prominent, especially the temperature and the concentration of the dilute sulfuric acid. The hydrolysis goes on efficiently when the temperature was higher than 100℃C, and the eellulose began to hydrolyze when it was higher than 110℃. The hydrolysis of corn stover was completed in 40 minutes; more hydrolyzing time cannot increase the hydrolysis rate. The proper concentration of sulfuric acid is 1.5%, higher concentration also cannot increase the hydrolysis rate. The solid content also influence the hydrolyzing process, lower solid content can acquire higher hydrolysis rate. From the experiment we also find the best treatment at following condition： 120℃, 80 min, 1.5 percent of diluted sulfuric acid, 10 percent of solid content in hydrolyzing process, and under this condition 32.71% reductive sugar in mass can be obtained compared with corn stover.