亚硫酸盐预处理对麦草组分分离和糖化的影响

通过正交实验设计,研究了亚硫酸盐预处理对麦草组分分离和糖化的影响,所考虑的主要因素是预处理温度、保温时间、亚硫酸氢钠用量及硫酸用量,极差分析结果表明这四个因素均影响麦草的糖化效率。升高温度、增加亚硫酸氢钠用量和硫酸用量、延长保温时间均能增加麦草的糖化效率,同时促进原料中木素和戊聚糖的溶出,但也会使戊糖发生进一步的转化。从原料中溶出戊聚糖和木素是麦草糖化效率提高的重要原因。在预处理温度180℃、亚硫酸氢钠用量3%、硫酸用量1.48%和保温时间20min条件下,酶水解后纤维素转化率为90.9%。

Effects of sulfite pretreatment on the components separation and saccharification of wheat straw

An orthogonal designed process was adopted to investigate the effects of sulfite pretreatment on the components separation and saccharification of wheat straw. Reaction temperature, retention time, charge of sodium bisulfite and charge of sulphuric acid were considered as the main influencing factors. The results of range analysis show that all the four factors have impact on the saccharification of wheat straw. Raising the temperature, increasing the charge of sodium bisulfite or sulphuric acid and extending the retention time can improve the dissolution of pentosan and lignin and the saccharification efficiency, while they can cause the further conversion of pentose. The separation of pentosan and lignin from wheat straw is the main cause to the improvement of saccharification. After enzymatic hydrolysis, cellulose conversion rate of 90.9% can be achieved by using the substrate pretreated under the condition of temperature 180℃, sodium bisulfite dosage 3%, sulfuric acid charge 1.48% and retention time 20min.