微波条件下纤维素在磷酸中的快速水解

微波条件下磷酸快速水解纤维素得到葡萄糖,而葡萄糖可替代甲醛制备新型环保PF(酚醛树脂)。以微波功率、反应时间和反应温度为试验因素,以葡萄糖产率为考核指标,采用正交试验法优选出磷酸水解纤维素的最佳工艺条件。结果表明:各因素对磷酸水解纤维素的影响依次为反应温度>反应时间>微波功率;当微波功率为240 W、反应温度为100℃和反应时间为40 s时,水解液中葡萄糖含量为80.7%,葡萄糖浓度为40.35 g/L;超声波能加快纤维素在磷酸中的溶解速率,常温时纤维素完全溶解在磷酸中需要72 h,而微波条件下纤维素完全溶解在磷酸中只需2 h。

Rapid hydrolysis between cellulose and phosphoric acid under microwave condition

The glucose,which was obtained by rapid hydrolysis between phosphoric acid and cellulose under microwave condition,can replace formaldehyde for preparing new environment-friendly PF(phenolic resin).With microwave power,reaction time and reaction temperature as experimental factors,glucose yield as evaluation index,the optimal process conditions of hydrolysis between phosphoric acid and cellulose were preferred by orthogonal experiment.The results showed that the influences of various factors on hydrolysis between phosphoric acid and cellulose were reaction temperature>reaction time>microwave power.The glucose contents and concentration were 80.7% and 40.35 g/L respectively in hydrolyzate when microwave power was 240 W,reaction temperature was 100 ℃ and reaction time was 40 s.The ultrasound can accelerate the dissolution speeds of cellulose in phosphoric acid,and the cellulose could completely dissolved in phosphoric acid after 72 h at room temperature or after 2 h at microwave.