Heterogeneous N-deacetylation of chitin in alkaline solution
Heterogeneous N-deacetylation of chitin in alkaline solution
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DOI：
10.1016/s0008-6215(97)00179-1
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发表时间：
1997-09-26
影响因子：
3.1
通讯作者：
Fu, WR
中科院分区：
文献类型：
--
作者：
Chang, KLB;Tsai, G;Fu, WR
研究了碱浓度、温度、液比对虾甲壳素N-脱乙酰化反应的影响。实验条件为10 ~ 60%NaOH，70 ~ 150 ℃，每克甲壳素加入5 ~ 45 mL碱性溶液。N-脱乙酰度主要随温度或NaOH浓度的升高而增加。溶液与甲壳素的比例的影响是不显著的。响应面分析表明，脱乙酰度最大发生在60%NaOH，107 ℃和26吨碱溶液每克甲壳素。表观速率常数范围为4.4 x 10（-5）至1.1 x 10（-2）min（-1）。在70-150 ℃的温度范围内，非均相N-脱乙酰化的活化能为56 kJ/mol。反应速率常数随碱浓度的增加而增大。碱浓度的影响表明，N-脱乙酰化可能是反应和扩散控制。(C)1997 Elsevier Science Ltd.
The influence of alkaline concentration, temperature and solution-to-chitin ratio on the N- deacetylation of shrimp chitin was investigated. Experimental conditions varied from 10 to 60% NaOH, 70 to 150 degrees C, and 5 to 45 mL of alkaline solution per gram of chitin, The degree of N-deacetylation increased mainly with increasing temperature or NaOH concentration. The effect of the solution-to-chitin ratio was insignificant. Response surface analysis indicated the maximal degree of deacetylation to occur at 60% NaOH, 107 degrees C and 26 mt alkaline solution per gram of chitin. The apparent rate constant ranged from 4.4 x 10(-5) to 1.1 x 10(-2) min(-1). In the temperature range of 70-150 degrees C, the activation energy for heterogeneous N-deacetylation is 56 kJ/mol. The rate constant also increased viith increasing alkaline concentration. The influence of alkaline concentration suggests that N-deacetylation might be both reaction and diffusion controlled. (C) 1997 Elsevier Science Ltd.