稻草酸水解制还原糖的工艺条件

研究了用稀H2SO4直接酸解稻草制还原糖的最佳条件,探讨了酸浓度、酸解温度和酸解时间等因素对还原糖含量的影响。实验表明,用稀H2SO4直接酸解稻草省去了预处理步骤,能获得较大的还原糖收率。采用正交实验法,以总还原糖浓度为考察指标,对实验结果进行方差分析,得出稀H2SO4酸解稻草的最适宜工艺条件为:硫酸质量分数20%,水解温度60℃,水解时间36h,稻草与硫酸量比为1∶10,可获得还原糖浓度为23.835g/L。对于稻草水解过程,认为4h前主要为半纤维素水解,16～36h主要为纤维素水解,36h后水解基本完成。

Study on Process of Reducing Sugar by Acid Hydrolysis of Rice Straw

The experiments of catalytic hydrolysis of rice straw by dilute sulfuric acid were performed.The influences of dilute sulfuric acid mass fraction,reaction temperature,reaction time on hydrolysis were discussed.The result showed that rice straw directly treated by dilute sulfuric acid can save the pretreatment step,and obtain good yield of reducing sugar.With the orthogonal test and the variance analysis of the experimental,the optimum reaction conditions were:dilute sulfuric acid mass fraction 20%,reaction temperature 60℃,reaction time 36 h,the ratio of solid to liquid(W/V)was 1∶10,the concentration of reducing sugar can reach 23.835 g/L.For the total progress,we believed that the hemicellulose acid hydrolysis was happened at the first 4 h,cellulose acid hydrolysis was between 16 h and 36 h,the whole progress was finished after 36 h.