碱/高温湿热法预处理玉米秸秆纤维素的研究

Study on pretreatment of corn straw cellulose with alkali/steam

研究了碱/高温湿热法对玉米秸秆的预处理效果;在预处理后的玉米秸秆中加入纤维素酶,考察此时酶解还原糖得率随预处理条件的变化;对NaOH浓度、固液比、加热时间3个因素进行单因素试验。试验结果表明,质量分数为4%的浓度下,糖得率最佳;酶解20 h后,固液比为1:10对酶解糖得率最高;加热时间为5 min时,酶解糖得率较大。设计正交试验对预处理的条件进行优化,得到水解玉米秸秆纤维素的适宜条件:NaOH质量分数为6%,固液比为1:10,加热时间为5 min。加入纤维素酶酶解,还原糖得率约为57%。通过对比改性预处理前后玉米秸秆的组分含量及SEM图,显示碱/高温湿热法对玉米秸秆有一定的处理效果破坏了玉米秸秆的原始表面结构,有利于酶解效果。

Corn straw cellulose was pretreated by the alkali/hot steam method.The effects of enzyme solution reducing sugar yield were studied after adding cellulase into the pretreated corn straw.The single factor tests have carried out on NaOH concentration,ratio of solid-liquid and heating time.The experiment result shows that the mass fraction is a concentration of 4%,sugar was best.Tthe ratio of solid to liquid was 1:10,the yield of enzymolysis sugar was the highest after 20 h.The heating time is 5 min,enzymatic hydrolysis sugar yield larger.The optimum conditions of the pretreatment of the corn straw were optimized by the orthogonal design.The NaOH mass fraction of 6%,the solid/water ratio is 1:10,the heating time was 5 min.The yield of reducing sugar was about 57%by the addition of cellulase.By comparing the change of pretreatment before and after corn straw group content and SEM,showed that alkaline/hot and humid method of corn straw has certain treatment effect destroyed the original surface structure of corn straw,is conducive to the enzymolysis effect.