盐酸降解甲壳素制备氨基葡萄糖盐酸盐的机理研究

Mechanism Study of Preparation of Glucosamine Hydrochloride from Chitin Degraded by Hydrochloric Acid

目的研究浓盐酸降解甲壳素制备氨基葡萄糖盐酸过程中反应体系变化,提出反应机理。方法通过设计甲壳素和浓盐酸在较低温度下的反应以及壳聚糖、壳寡糖和N-乙酰氨基葡萄糖在盐酸中的反应并对反应过程分析。结果甲壳素在较低温度下与浓盐酸主要发生降解反应,壳聚糖、壳寡糖在同样条件下不容易与浓盐酸发生降解反应,N-乙酰氨基葡萄糖同样条件下容易发生脱乙酰基反应。结论浓盐酸降解甲壳素的反应过程以降解为主要反应,脱乙酰反应为次要反应,该机理的研究为工艺优化提供理论依据。

OBjECTIVE To research the change of the reaction of chitin degraded by hydrochloric acid and present the mechanism of the reaction. METHODS The study design four experiments of the reactions of hydrochloric acid in moderate temperature with chitin, chitosan, oligochitosan and N-acetyl-D-（ ＋ ）-glucosamine （NAG） respectively. RESULTS It is found that chitin is easy to be degraded in hydrochloric acid, the chitosan and oligochitosan are difficult to be degraded, but the NAG is easy to have the deacetylation reaction. CONCLUSION The degradation is the most important and the deacetylation is secondary in the reaction of chitin with hydrochloric acid.