仿生吸附结构磁基聚合物对重金属微污染水的强化絮凝

Heavy metal is one of the main pollutants of micro-polluted source water, and conventional flocculation-precipitation processes are difficult to effectively remove dissolved ions and organics in water. Based on the fact that the existing flocculants have single treatment effect, limited application range and high treatment cost, the project is devoted to the development of an environmentally friendly renewable flocculant with a strong characteristic adsorption structure, which is expected to simplify the processes of pretreatment and advanced treatment by enhanced flocculation. The project imitates the concept of octopus tentacles，and it is intended to greatly increase the adsorption active sites of polymer molecular chains by chemical modification such as carboxymethylation, xanthogenation of chitosan and graft copolymerization of polymers on the surface of magnetic cores so as to achieve the flocculant with strong adsorption-bridge action, magnetic separation and recyclability. In addition, by evaluating the flocculation performance of the target flocculant on composite heavy metal ions and heavy metal/organic composite pollutants in water, the structure-effect relationship between the flocculant biomimetic adsorption structure and flocculation performance was discussed, and the enhanced flocculation mechanism and the competition-synergistic behavior between the pollutants were revealed. The expected results of this project can provide theoretical basis and technical support for the development of water treatment agents and the effective control of heavy metal micro-pollution in water.

重金属是微污染源水的主要污染物之一，常规絮凝沉淀工艺难以有效去除水中溶解性离子和有机物。基于现有絮凝剂存在处理效果单一、应用范围受限、处理成本高等问题，该项目致力于开发一种具有强吸附特性结构的环境友好型可再生絮凝剂，有望通过强化絮凝来简化预处理和深度处理工艺。项目模仿章鱼触手理念，拟通过壳聚糖羧甲基化、黄原酸化和磁核表面聚合物的接枝共聚等化学改性来大量增加聚合物分子链的吸附活性位点，从而实现絮凝剂的强吸附-桥连作用、磁分离性和重复利用性。此外，通过评价目标絮凝剂对水中复合重金属离子和重金属/有机物复合污染物的去除性能，探讨絮凝剂仿生吸附结构与絮凝性能之间的构-效关系，深入阐明其强化絮凝机理并揭示污染物间的竞争/协同絮凝行为。该项目预期成果可为水处理剂的研发和水体重金属微污染的有效控制提供理论依据和技术支撑。

常规絮凝剂难以有效去除水中重金属离子和有机物。通过借鉴章鱼触手的自然生理结构，项目致力于开发了系列具有强吸附特性结构的环境友好型可再生絮凝剂，通过强化吸附功能基团来拓展絮凝剂的性能。项目系统地研究了强吸附结构磁基壳聚糖聚合物的递进分子设计与结构性质分析，实现了对水中重金属离子和有机污染物的增效去除，通过絮体结构成分发现各富电子基团(如-COOH、-OH、-NH3+/ -NH2和-N+-(CH3)3基团等)是絮凝过程中的关键吸附位点，絮凝剂具有较好地重复回用性能。此外，项目还拓展了细菌产藻酸盐基水凝胶合成的生物质策略及对重金属的吸附去除研究，将水处理剂制备往剩余污泥中生物聚合物的资源化方向发展，有望实现“以废制废”。项目研究成果在一定程度上为水处理剂研发和水体重金属复合污染的有效控制提供了理论依据和技术支撑。在项目资助下共发表了论文16篇，其中项目负责人以第一作者或通讯作者身份发表SCI论文12篇，获得授权国家发明专利1项。