A novel thymine-containing chitosan derivative has been designed, synthesized, and used for the first time in this work for removal of some commercial pesticides from synthetic wastewater by coagulation/flocculation. The chitosan-thymine conjugate was characterized by ¹H NMR and FT-IR spectroscopy, and its flocculation performance was evaluated by UV–Vis spectroscopy in comparison to non-modified chitosan. The commercial pesticides used in this investigation were Fastac 10 EC and Karate Zeon (with alpha-Cypermethrin and lambda- Cyhalothrin, respectively, as active pyrethroid ingredients), Novadim Progress (Dimethoate as active organophosphoric ingredient), and Bordeaux mixture. The experimental results demonstrate good removal efficiency for Karate Zeon (between 80 and 85%), a maximum of around 90% for Fastac 10EC and Novadim Progress, and more than 95% for the Bordeaux mixture, irrespective of the polycation structure. According to the zeta potential values recorded in the optimum dose interval, the flocculation of pyrethroid pesticides particles took place mainly by means of the charge neutralization mechanism (close to zero), whereas the flocculation of Novadim Progress and Bordeaux mixture particles has been achieved by the synergistic effect of charge neutralization and hydrogen bonding (Novadim Progress) or copper ion binding by the amine and thymine groups (Bordeaux Mixture) (negative values).

已经设计，合成了一种新型的含胸腺嘧啶的壳聚糖衍生物，并将其首次用于通过混凝/絮凝从合成废水中去除一些商业农药的方法。壳聚糖-胸腺嘧啶结合物的特征是¹H NMR和FT-IR光谱，其絮凝性能通过UV-Vis光谱与未改性的壳聚糖相比进行了评估。本次调查中使用的商业农药为Fastac 10 EC和空手道Zeon（分别以α-氯氰菊酯和lambda-氯氟氰菊酯作为拟除虫菊酯的活性成分），Novadim Progress（杀灭草酸盐为有机磷的有效成分）和波尔多的混合物。实验结果表明，空手道Zeon的去除效率良好（介于80％和85％之间），Fastac 10EC和Novadim Progress的去除效率最高，大约为90％，而波尔多混合物的去除效率则高达95％以上，与聚阳离子的结构无关。根据最佳剂量间隔中记录的Zeta电位值，