以玉米淀粉（St）为原料、2，3-环氧丙基三甲基氯化铵（GTA）为醚化剂，利用湿法合成高取代度的阳离子醚化淀粉絮凝剂St-GTA。通过正交实验对St-GTA的合成条件进行筛选，结果表明，最佳合成条件为：n（CTA）：n（St）=1.2：1、m（NaOH）：m（St）=0.08：1、反应温度为70℃、反应时间为3 h。在该条件下合成的产物取代度可达0.717 3。以高岭土悬浊液为模拟污水，考察了絮凝剂投加量、絮凝体系pH、絮凝温度、絮凝时间对絮凝效果的影响。结果表明，对于质量分数为2%的高岭土悬浊液，当pH=7、絮凝温度为25℃、絮凝时间为0.5 h时，St-GTA的最佳质量浓度为8 mg/L，透光率可达92.81%。

St-GTA,an etherified starch flocculant with high substitution degree is synthesized by the wet-route method with corn starch (St) as raw material and 2,3-epoxypropyl trimethylammonium chloride (GTA) as etherifying agent.The synthetic conditions of St-GTA are screened via orthogonal experiment.The optimum synthetic conditions are found as follows:n(CTA):n(St)=1.2:1,m(NaOH):m(St)=0.08:1,reaction temperature is set at 70℃ and reaction time is 3 h.The substitution degree of products can achieve 0.717 3 under the optimum conditions.Taking kaolin suspension as simulated wastewater,the influences of the dosage of flocculant,pH value of flocculation system,flocculation temperature and flocculation time on flocculation efficiency are investigated.The results indicate that the transmittance can reach 92.81% for 2wt% kaolin suspension when pH=7,flocculation temperature is at 25℃,flocculation time is 0.5 h,and the optimum dosage of St-GTA is 8 mg·L^-1.

李海花(1979-),女,博士,副研究员,研究方向为绿色水处理剂的研究与开发,873756647@qq.com