阳离子淀粉-膨润土复合絮凝剂对活性染料的吸附

针对膨润土和阳离子淀粉单独用于处理印染废水时存在脱色率低和固液难分离的问题，采用一步法将阳离子淀粉和膨润土同时投入到活性红X-3B的染色废水中，使阳离子淀粉与膨润土相互吸附，形成结构疏松、比表面积较大的阳离子淀粉-膨润土复合絮凝剂，同时吸附废水中的染料，对其进行脱色。以阳离子淀粉-膨润土复合絮凝剂对活性红X-3B染料废水的脱色率为考核指标，经过实验研究，确定了最佳的应用工艺：阳离子淀粉与膨润土在染料废水中的投加量总量为1.25 g/L，阳离子淀粉与膨润土的质量配比为1:1,印染废水的pH 值为7，不添加氯化钠，处理后印染废水的脱色率可达90%以上。在此基础上通过建立等温吸附曲线，确定了阳离子淀粉-膨润土复合絮凝剂的等温吸附线为典型的L-型，属于表面配位吸附。

Application of cationic starch-bentonite composite to adsorb Reactive Red X-3B dye

A novel compound flocculant was prepared using one-step process with the natural bentonite and cationic starch adsorbed for each other, in order to increase the color removal efficiency of bentonite and cationic starch, respectively. The mixture of cationic starch and bentonite had a large specific surface area and loose structure, which increased the effect of adsorption for dye. An indicator of the percentage of color removal was used to determined the optimal application conditions of cationic starch –bentonite compound through experiments: the dosage of adsorbent was 1.25g.L-1 with a mass ratio of 1:1, the pH of dyeing wastewater was 7, without additional sodium chloride, and its color removal rate from wastewater of reactive red X- 3B was more than 90%. On this basis, the adsorption isothermal line of the cationic starch-bentonite compound was set, which belonged to L-model, and the adsorbent’s adsorption of the reactive red X- 3B is coordinated surface adsorption.