壳聚糖席夫碱类絮凝剂的制备及性能研究

Preparation and Properties of Chitosan Schiff Base Flocculants

以戊二醛和壳聚糖(CTS)为原料,合成了壳聚糖席夫碱(G-CTS)。通过单因素实验,探讨最佳反应条件。利用黏度法和修订的Mark-Houwink公式,得壳聚糖席夫碱的黏均分子量和产物的缩合率。通过红外光谱(FTIR),X射线衍射(XRD)和扫描电子显微镜(SEM)表征其结构。FTIR以及XRD谱图结果均表明壳聚糖发生了接枝和交联反应,SEM观察到其孔洞结构的增加。利用紫外光谱分析改性前后壳聚糖对水溶性染料的絮凝效果。实验结果显示,用戊二醛交联壳聚糖可以生成不同缩合率的壳聚糖席夫碱,对水溶性阴离子偶氮染料有优良的选择性和吸附作用,其中甲基橙24 h去除率达82.08%,7天去除率达到98.60%。

Chitosan Schiff base(G-CTS)was synthesized from glutaraldehyde and chitosan(CTS).The optimum reaction conditions were discussed by single factor experiment.The viscosity average molecular weight and condensation rate of chitosan Schiff base were calculated by viscosity method and modified Mark-Houwink formula.The structure was characterized by infrared spectroscopy(FTIR),X-ray diffraction(XRD)and scanning electron microscopy(SEM).The results of FTIR and XRD showed that graft and crosslinking reaction took place,and the increase of pore structure was observed by SEM.The flocculation effect of chitosan on water-soluble dyes before and after modification was analyzed by UV spectrum.The results showed that chitosan Schiff bases with different condensation rates could be formed by crosslinking chitosan with glutaraldehyde.It had excellent selectivity and adsorption for water-soluble anionic azo dyes,and the removal rate of methyl orange was 82.08% in 24 h and 98.60% in 7 days.