13X分子筛催化降解纤维低聚糖的研究

13X Zeolite Catalyzed Degradation of Cellooligosaccharides

研究探讨了在反应时间0.5-16h、催化剂用量0.1-0.4mg/mL、反应温度40-100℃和初始纤维低聚糖浓度0.8-3.2 mg/mL的条件下,13X分子筛催化纤维素模型物纤维三糖的降解情况。通过降解产物的液相色谱分析发现：在13X分子筛催化纤维三糖降解过程中会产生纤维二糖和葡萄糖,同时会产生其他未被鉴定的降解产物;纤维三糖的水解反应和降解反应同时发生;13X分子筛的催化活性与纤维低聚糖的聚合度有关,不能催化更高聚合度低聚糖的水解和降解,例如当催化纤维四糖和纤维五糖时,无葡萄糖和更低聚合度的纤维低聚糖产生。

The degradation of cellotriose, a model system for cellulose, was investigated over 13X zeolite catalyst. The product distributions were discussed with reaction times from 0.5h to 16h, zeolit dosages from 0.1g/mL to 0.4g/mL, temperatures from 40℃ to 100℃, and initial cellotriose concentratioins from 0.8mg/mL to 3.2mg/mL. HPLC analysis showed that during the degradation, cellobiose and glucose were released. Furthermore, other unknown degradation products were also detected by HPLC. Product distributions indicated that the reaction occurred consisted of hydrolysis and degradation of cellotriose in the presence of 13X zeolite. The activity of 13X zeolite was correlated with the degree of polymerization （DP） of cellooligosaccharides. No degradation and hydrolysis reactions occurred when the oligosaccharides with DP higher than three were catalyzed by 13X zeolite. For example, there were no glucose and smaller oligosaccharides produced when cellotetraose and cellopentaose were degradated by the zeolite.