论文部分内容阅读
本研究通过几种纤维素的模型化合物(左旋葡聚糖、纤维二聚糖、纤维三聚糖、纤维四聚糖、葡萄糖、纤维二糖、纤维三糖)在Py-GC—MS上的快速热解实验,通过研究其热解产物的分布规律并比较几种主要产物的峰面积绝对值的变化,来揭示纤维素热解过程中糖类的生成机理及转化途径。实验结果表明,脱水糖和原糖在热解产物分布上存在很大的差异,原糖和脱水糖相比较,产物中糖类的峰面积百分比明显降低,伴随的是呋喃类的峰面积的明显增加;原糖中,5-羟甲基糠醛和糠醛产率均随着聚合度的升高而增加,脱水糖中则相反。两类糖的左旋葡聚糖的产率随着聚合度的升高增加,而左旋葡聚糖酮的产率随着聚合度的升高呈现相反的趋势。
In this study, the rapidity of Py-GC-MS on model compounds of several celluloses (levoglucosan, cellobiose, cellotriose, cellotriose, glucose, cellobiose and cellotriose) Pyrolysis experiment, by studying the distribution of pyrolysis products and compare the absolute value of the peak area of several major products, to reveal the mechanism of carbohydrate generation and transformation pathway in the cellulose pyrolysis process. The experimental results show that there is a great difference in the distribution of pyrolysis products between dehydrated sugar and raw sugar. Compared with dehydrated sugar, the percentage of peak area of sugars in the product is obviously decreased, accompanied by the obvious peak area of furan Increase; raw sugar, 5 - hydroxymethyl furfural and furfural yield increases with the degree of polymerization increases, dehydration sugar is the opposite. The yield of both types of sugar levoglucosan increased with the increase of the degree of polymerization, whereas the yield of levodone showed the opposite trend with the increase of the degree of polymerization.