负载纳米Fe/Pa新型温敏复合水凝胶的制备及其还原脱氯反应调控机理研究

Waste water which contains chlorinated organic compounds remediation by nanoscale zero-valent iron has received increasing attention in recent years.However, nanoscale zero-valent iron tends to aggregate together due to its high surface energy and intrinsic magnetic interaction，which results in an adverse effect on removal efficiency.So it is interesting to develop a supporting material to enhance the activity and reusability of nanoscale zero-valent iron.Temperature responsive hydrogels are used as reactive nanoparticle supports not only easy to get the particle size, morphology controllable nanoparticles, and effectively prevent agglomeration of nanoparticles, and facilitate recycling and reuse nanoparticles but also to control the properties of nanoparticles by changing the ambient temperature. In current research, novel temperature responsive hydrogels with chelating ability and responsive temperature in line with the actual water temperature will be synthesized by compolymerization of diacetone acrylamide and N-(4-vinylbenzyl) iminodiacetic acid. Temperature responsive composite hydrogels which have high load rate, ion recovery capability and can be used repeatedly will be prepared via in-situ reduction method, based on temperature responsive hydrogels used as the load of iron and palladium nanoparticles carrier materials. The effects of experimental parameters on the efficiency of trichlorothylene reductive dechlorinated and the reductive dechlorination reaction kinetics will be investigated in details. As the key points, the regulation mechanisms of reductive dechlorination reaction will be studied. The project is carried out to provide a theoretical basis and technical guidance for the design of intelligent hydrogels-suppored reactive nanoparticles and its application in dechlorination of water.

利用纳米级零价铁去除水体中的氯代烃近年来日益受到关注,但纳米铁粒子易团聚、易氧化、稳定性差，因此，采用合适的载体材料和负载方法，制备出性能稳定、反应活性高负载纳米铁是纳米铁在实际水处理中必须解决的问题之一。温敏水凝胶作为纳米铁粒子的载体材料可得到粒径、形貌可控的纳米微粒，有效避免纳米微粒团聚，并有利于纳米粒子的回收和重复使用，还可以实现对纳米粒子性能的有效调控。本项目拟利用价廉易得的双丙酮丙烯酰胺和N-(4-乙烯基苄基)亚氨基二乙酸为原料，设计合成出螯合能力强、体积相转变温度符合实际水处理要求的温敏水凝胶，并用其作为负载纳米铁和钯的载体材料制备负载率高、离子回收能力强，可多次重复使用的温敏复合水凝胶。将该材料应用于处理水体中的三氯乙烯，考察还原脱氯效果并研究其调控机理。本项目的开展为智能水凝胶负载反应性纳米粒子材料的科学研究及其在水体中氯代有机污染还原脱氯降解中的应用提供理论基础和技术。

利用纳米级零价铁去除水体中的氯代烃近年来日益受到关注，但纳米铁粒子易团聚、易氧化、稳定性差，因此，采用合适的载体材料和负载方法，制备出性能稳定、反应活性高负载纳米铁是纳米铁在实际水处理中必须解决的问题之一。温敏水凝胶作为纳米铁粒子的载体材料可得到粒径、形貌可控的纳米微粒，有效避免纳米微粒团聚，并有利于纳米粒子的回收和重复使用，还可以实现对纳米粒子性能的有效调控。本项目首先利用价廉易得的双丙酮丙烯酰胺为原料设计合成出一种低临界溶解温度（LCST）可调控的新型温敏大分子单体，系统研究了温敏大分单体的温度刺激响应性，研究表明，该温敏大分子单体的LCST可以通过调整大分子单体中双丙酮丙烯酰胺比例有效调控；以上述合成的温敏大分子单体为原料设计合成具有温度响应的互穿网络水凝胶，探讨了互穿网络水凝胶溶胀性能、温度响应性能及热稳定性等，结果表明，互穿网络水凝胶具有明显的温度响应性能，通过调节环境温度进而调控水凝胶性能；以互穿网络水凝胶为负载纳米铁和钯的载体材料制备负载率高、离子回收能力强，可多次重复使用的温敏复合水凝胶，将该材料应用于处理水体中的三氯乙烯，考察还原脱氯效果并研究其调控机理，研究表明，该负载纳米Fe/Pd温敏复合水凝胶材料对溶液中三氯乙烯的去除效果有显著影响，去除率可达85%以上。本项目的开展为智能水凝胶负载反应性纳米粒子材料的科学研究及其在水体中氯代有机污染还原脱氯降解中的应用提供了理论基础和技术。