低聚壳聚糖制备液纳滤纯化的可行性研究

通过对筛选的3种纳滤膜结构及对低聚壳聚糖、氨基葡萄糖和NaAc溶液的截留性能和纯化过程研究发现,3种纳滤膜的膜面粗糙度大小依次为:DL>DK>NTR-7450,均能对低聚壳聚糖100%截留,但只能部分截留氨基葡萄糖和NaAc,其截留率大小为:DK>DL>NTR-7450。从低聚壳聚糖的纯化工艺要求和抗污染能力方面考虑,NTR-7450纳滤膜更具有工业应用价值。此外,纳滤膜对溶质的分离效果主要由空间位阻和静电效应决定,综合作用结果导致了低聚壳聚糖体系中的各种主要阳离子在纳滤过程中存在竞争透过,截留次序依次为:高分子低聚壳聚糖>氨基葡萄糖>Na+>H+。在Donnan效应和电离平衡的影响下,体系中Ac-在纳滤过程中也被脱出。纳滤纯化低聚壳聚糖制备液在技术上可行。

FEASIBILITY STUDY ON CHIITOOLIGOSACCHARIDES PURIFICATION BY NANO-FILTRATION MEMBRANES

The structure performance of three NF membranes and their rejection characteristics to Chiitooligosaccharides(COS) were researched.The experimental results showed the order of roughness of NF membranes surface was as followings: DL>DK>NTR-7450,and the rejection efficiency of these three NF membranes to COS could be up to 100%,but that only part of glucosamine and NaAc could be rejected,and the order of rejection efficiency was DK>DL>NTR-7450.From the view point of the purification aim of COS and anti-fouling capacity of NF membrane,NTR-7450 had a bigger industry application value.Furthermore,the steric and electrostatic effects were dominant for solute separation effect to nano-filtration membranes and there was competition-penetration among cation in the course of nano-filtration.The order of nano-filtration membranes rejection to cation in COS solution was COS>monosaccharide>Na+>H+.At the same time,Ac-could be removed from COS solution under Donnan effect and ionization equilibrium.So it was feasible that NF purified COS solution.