ATRP法制备离子交换膜应用于扩散渗析和电渗析

发布时间：2018-06-12 09:21

本文选题：原子转移自由基聚合 + 阳离子交换膜　；参考：《合肥工业大学》2015年硕士论文

【摘要】：在现代工业如钢铁、冶金等行业生产过程中,常常会产生大量废液。如果这些废液没有处理就直接排放,不但浪费了废液中的有用资源,而且会严重污染环境和水源。扩散渗析(DD)是一种低操作费用的分离过程,驱动离子透过膜的动力主要是渗透侧和扩散侧的浓度差,因而能耗很低。DD过程还具有清洁、易操作等优点。因此DD是解决废液问题的一种简单有效且经济环保的方法。另外,近年来许多特种分离领域的应用需求亟需满足,例如海水淡化过程往往希望离子交换膜能够实现不同价态离子的选择性分离,从复杂的水盐溶液中分离特定的离子。电渗析(ED)是在直流电场的作用下,离子透过离子交换膜进行迁移的过程,具有能耗低、操作简便、使用寿命长、无污染等特点。在ED过程中,选择透过性膜对不同价态离子的传输性能不同,从而使其分离。因此,制备出相应的选择性离子交换膜对电渗析分离一二价离子具有重大的意义。普通原子转移自由基聚合(ATRP)以及电子转移活化再生催化剂原子转移自由基聚合(ARGET-ATRP)是近年来迅速发展并具有重要应用价值的活性聚合方法,这种方法不仅可以控制聚合物的分子量和聚合链的多分散性,而且对聚合物的组成、结构和端基官能团也实现了控制。通过这种方法还可以制备预定结构和序列的嵌段和接枝共聚物。本论文一共包括五章。第一章是绪论,大体分为两个部分。第一部分介绍目前工业废液的危害和常规处理办法,扩散渗析(DD)方法、装置以及ATRP、 ARGET-ATRP。第二部分介绍一二价离子选择性膜的应用价值、制备方法以及电渗析(ED)等。第二章探索通过几种ATRP方法制备聚苯乙烯磺酸钠(PSSS)。包括：利用普通ATRP方法通过2-溴代异丁酸乙酯(EBiB)引发苯乙烯磺酸钠(SSS)聚合；以溴化聚(2,6-二甲基-1,4-苯醚)(BPPO)上的PPO-CH2Br为大分子引发剂,通过ARGET ATRP聚合,在BPPO高分子链上接枝引入SSS；以及利用EBiB引发SSS进行ARGET ATRP聚合。前两种方法都存在一定的不足,第三种方法可以成功制备得到聚电解质(PSSS)。第三章将聚电解质(PSSS)与聚乙烯醇(PVA)共混,并用硅烷偶联剂交联,涂膜后干燥、热处理得到阳离子交换膜。我们从水含量、65℃水中溶胀性能、离子交换容量(IEC)等方面对膜的性能进行表征,并将其应用于扩散渗析(DD)过程,处理模拟工业废水(NaOH/Na2WO4)体系。膜中PVA基体亲水性较强,且能提供大量羟基(-OH),对水合离子如OH-的渗析通量较高；PSSS组分含有大量离子交换基团,提高了膜的渗析通量和离子选择分离特性；硅烷偶联剂可以进行交联,克服了膜溶胀度高的缺点。第四章讲述了通过SI-ATRP方法在商业溴化聚(2,6-二甲基-1,4-苯醚)(BPPO)膜上接枝聚合SSS,再对BPPO基体进行季铵化。这样膜的主体带有大量的正电荷(-N+(CH3)3),而表面接枝了一层负电荷(-S03-)。我们从水含量、离子交换容量(IEC)、热稳定性、离子迁移数等方面对膜进行表征,并通过对NaCl/Na2SO4体系进行电渗析(ED)探究,考察膜对一二价阴离子的分离选择性能。第五章是对全文的总结。对如何通过ATRP方法制备离子交换膜,以及该种膜在DD和ED应用前景等方面进行了分析和总结,得出一些有意义的结论。
[Abstract]:In the production process of modern industry, such as iron and steel, metallurgy and other industries, a lot of waste liquid is often produced. If the waste liquid is not treated, it will be discharged directly, not only waste the useful resources in the waste liquid, but also seriously pollute the environment and water source. Diffusion dialysis (DD) is a low operating cost separation process, the driving ion transmission through the membrane is the main power. It is the poor concentration of the osmotic side and the diffusion side, so the energy consumption is very low.DD process is also clean and easy to operate. So DD is a simple and effective and economical method to solve the problem of waste liquid. In addition, in recent years, many special separation fields need to be satisfied. For example, the process of seawater desalination often hopes the ion exchange membrane can be used. Selective separation of valence ions and separation of specific ions from complex water and salt solutions. Electrodialysis (ED) is a process of migration of ions through ion exchange membranes under the action of direct current electric field. It has the characteristics of low energy consumption, easy operation, long service life and no pollution. In the process of ED, the selective permeable membrane is selected for different valence states. The transfer properties of ions are different and thus make them separate. Therefore, the preparation of the corresponding selective ion exchange membrane is of great significance for the separation of one or two valence ions by electrodialysis. The common atom transfer radical polymerization (ATRP) and the atom transfer free radical polymerization (ARGET-ATRP) of the electron transfer activation regeneration catalyst have developed rapidly in recent years. The method of active polymerization, which is of important value, can not only control the molecular weight of the polymer and the polydispersity of the polymer chain, but also control the composition of the polymer, the structure and the functional group of the end group. In this way, the block and graft copolymers of the predetermined structure and sequence can be prepared. This paper includes five Chapter 1 is the introduction, which is divided into two parts. The first part introduces the hazards and conventional treatment methods of industrial waste liquid, diffusion dialysis (DD) method, device and ATRP, ARGET-ATRP. second, introduces the application value, preparation method and electrodialysis (ED) of the one or two valence ion selective membrane. The second chapter explores through several ATRP parties Sodium polystyrene sulfonate (PSSS) was prepared by the method, including the polymerization of sodium phenylene sulfonate (SSS) by 2- bromide ethyl (EBiB) by common ATRP method, and PPO-CH2Br as a large molecular initiator with brominated poly (2,6- two methyl -1,4- phenyl ether) (BPPO). IB leads to SSS for ARGET ATRP polymerization. The first two methods have some shortcomings, the third methods can successfully prepare polyelectrolyte (PSSS). In the third chapter, polyelectrolyte (PSSS) and polyvinyl alcohol (PVA) are blended and crosslinked with silane coupling agent, after coating the film and heat treatment to get the cation exchange membrane. We are from water content, 65 C water. The properties of the membrane are characterized by swelling properties and ion exchange capacity (IEC), and they are applied to the diffusion dialysis (DD) process to treat the simulated industrial wastewater (NaOH/Na2WO4) system. The hydrophilic property of the PVA matrix in the membrane is stronger and can provide a large number of hydroxyl groups (-OH), and the permeability of the hydrated ions, such as OH- is higher, and the PSSS component contains a large amount of ion exchange. In the fourth chapter, the fourth chapter describes the grafting of SSS on the commercial brominated poly (2,6- two methyl -1,4- phenyl ether) (BPPO) membrane through the SI-ATRP method and the quaternification of the BPPO matrix. The main body of the membrane is the main body of the membrane. A large number of positive charges (-N+ (CH3) 3) and a layer of negative charge (-S03-) are grafted on the surface. We characterize the membrane from water content, ion exchange capacity (IEC), thermal stability, ion migration number and so on. The separation and selection performance of the membrane to one or two valence anions is investigated by conducting electrodialysis (ED) on the NaCl/Na2SO4 system. The fifth chapter is the full text The analysis and summary on how to prepare ion exchange membrane by ATRP method and the application prospect of this kind of membrane in DD and ED are analyzed and summarized, and some meaningful conclusions are drawn.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ028.7

【参考文献】