离子交换法的发展趋势及应用

离子交换法是利用离子交换剂与溶液中的离子发生交换作用而使离子分离的方法。如今,离子交换分离技术取得了突飞猛进的发展,成为了现代各个工业中净化与分离的中流砥柱。阐述了离子交换分离法的发展以及最新的应用进展,从重金属污水处理、食品工业、医药卫生以及清洁能源等方面综合阐明离子分离技术以及离子交换树脂在诸多领域中的重要作用。     

离子交换纤维吸附辣椒碱的动力学

采用SEM和IR方法表征了吸附辣椒碱前后的ZB-2强碱性阴离子交换纤维,确定了可以吸附;然后测定了离子交换纤维吸附辣椒碱的速率,确定了吸附在3 min时由液膜扩散控制转入离子交换纤维内扩散控制;最后考察了搅拌速度、溶液浓度和吸附温度对速率的影响,得到了离子交换纤维内扩散控制交换过程的表观活化能、反应级数、速率常数和动力学方程式。     

Synthesis and cation exchange properties of a new porous cation exchange resin having an open-celled monolith structure

We succeeded in introducing cation exchange groups quantitatively into a porous resin having an open-celled monolith structure. The resulting new cation exchange resin had the following advantages compared with conventional ion exchange resins having a bead structure. First, it was easier to pack it in a column. Second, the ion exchange rate of the new cation exchange resin was much higher than that of the conventional ion exchange resins, and the ion exchange band length of the new resin was smaller than that of the conventional ones. In addition, the electric conductivity was about five times higher than that of the conventional ones, although they had similar ion exchange capacities. These unique properties of the new cation exchange resin were caused by the quantitative introduction of ion exchange groups into the resin having the open-celled monolith structure.     

弱酸树脂处理"负硬水"

用H 柱-脱气塔-Na 柱串联工艺处理"负硬水".H 柱浮动床,Na 柱固定床,均采用弱酸性阳离子交换树脂110.处理后的水在满足硬度要求的同时,碱度＜1.0 mmol/L,出水体积可高达H 交换柱树脂体积的260倍以上.运行结果表明,工艺具有操作简便、出水稳定、水质良好等优点,是处理"负硬水"非常好的方法.     

离子交换层态分析和逆流再生技术的探讨

本文从离子交换动力学和色层理论出发，分析离子交换过程中树脂层形态的变化，从理论上剖析顺流再生、逆流再生技术的优、缺点。     

D296树脂分离锆、铪洗脱的效果

介绍了在离子交换固定床上用D296强碱性阴离子交换树脂分离锆、铪的洗脱实验研究。吸附与洗脱实验的温度均控制在2~5℃,洗脱实验在饱和吸附的离子交换柱、过漏的离子交换柱、未过漏的离子交换柱中进行。研究结果表明:离子交换柱吸附状态以及洗脱剂酸度对分离效果有显著的影响。当离子交换柱存在交换区时,用任何酸度的硫酸作为洗脱剂,铪均被先洗脱出来,但高酸度的洗脱剂对分离锆、铪更有利;当离子交换柱为饱和状态时,低酸度和高酸度的洗脱剂洗脱,锆、铪不能得到分离。实验证明了单一的固定床分离锆、铪的效率低,要成功实现锆、铪的分离,需采用连续分离的离子交换移动床。     

低湿条件下离子交换纤维吸附性能的研究

以超高交联聚丙烯-苯乙烯-二乙烯基苯(PP-ST-DVB)纤维为母体,分别经磺化、氯甲基化和胺化反应制得强酸或强碱离子交换纤维;研究了在低湿条件下对酸碱有害气体的动态吸附性能。结果表明:强酸离子交换纤维(交换容量为2.92 mmol/g)对NH_3气体的穿透吸附量约为40.95 mg/g,高于Fiban K-1磺酸型离子交换纤维的穿透吸附量;强碱离子交换纤维对SO_2气体的穿透吸附量约为77.50 mg/g,是Fiban A-1强碱离子交换纤维的1.55倍,自制的强酸、强碱离子交换纤维可多次再生使用。     

Evaluation of heavy metal kinetics through pyridine based Th(IV) phosphate composite cation exchanger using particle diffusion controlled ion exchange phenomenon

In this study, the ion exchange kinetics of selected heavy metals such as Cd, Cu, Pb and Zn through the pyridine based thorium(IV) phosphate composite cation exchange material was studied. The ion exchange kinetics over this composite cation exchanger followed the particle diffusion controlled ion exchange phenomenon. Kinetics parameters also revealed that the mechanism of ion exchange for heavy toxic metal ion is feasible to explore the wastewater treatment.     

离子交换树脂在过氧化氢净化中的应用进展

介绍了离子交换树脂净化过氧化氢的原理,总结了近年来离子交换树脂净化技术的应用情况,主要评述了阴、阳离子交换树脂结合净化、离子交换树脂与辅助试剂结合净化、离子交换树脂与其他技术集成净化,并指出了今后的研究方向：     

离子交换树脂催化酯化研究进展

与传统的无机催化剂相比,离子交换树脂表现出良好的催化性能并且能回收再利用。本文简单介绍了离子交换树脂的种类,重点介绍了离子交换树催化剂在酯化反应中的应用进展。     

Influence of doping anions on the ion exchange behavior of polypyrrole

The ion exchange behavior of polypyrrole (PPy) doped with a variety of dopants (A), namely chloride, nitrate, para‐toluene sulfonate (pTS^?), and dodecyl sulfonate (DS^?), was investigated by means of cyclic voltammetry (CV) in NaCl, NapTS, and AlCl₃ aqueous solutions. The results show that PPy/pTS and PPy/DS films had the best anion and cation exchange ability, respectively. However, the ion exchange ability evaluated by CV charge cannot describe the exact amount of exchanged ions. For that reason, a new ion exchange experiment was designed to evaluate the amount of ions removed from NaCl aqueous solution to AlCl₃ or NapTS aqueous solution. In addition, the ion exchange ratio is defined as the ratio of the charge associated with ion ejection to the synthesis charge, and can be conveniently converted to operating exchange capability (OEC). The ion exchange ratio and OEC can be used to characterize and evaluate the ion exchange ability of PPy/A films in different conditions. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Ion exchange membranes and separation processes with chemical reactions

Recent research trends in the development of ion exchange membranes and their use in separation processes with chemical reactions are reviewed. Emphasis in research on the ion exchange membrane is trending toward analysis of micro-structure of the membranes and to development of new functionalized ion exchange membranes in response to industrial requirements. Separation processes with chemical reactions are discussed according to the following classifications: (1) double decomposition of electrolytes; (2) production of acid and base by bipolar ion exchange membrane processes; (3) separators for electrolysis; (4) separators for batteries; (5) use as solid polyelectrolytes; (6) active transport through ion exchange membranes; (7) acceleration of chemical reactions by ion exchange membranes; (8) carrier transport in ion exchange membranes; (9) transducers for electrical signals from chemical reactions; and (10) modified electrodes.     

Modeling of Reactive Diffusion in Glass‐Ceramics

A model of reactive ion‐exchange diffusion in glassy materials (glasses and glass‐ceramics) has been developed. The model can be used to simulate the processes of ion‐exchange‐induced decrystallization of glass‐ceramics and ion‐exchange‐induced glass crystallization. Analysis of the model in dimensionless form resulted in determining a set of dimensionless complexes comprising dimensional parameters of the ion exchange system (diffusivity, rate constant of grain dissolution, initial size and composition of the crystalline grains, etc.). Numerical values of the complexes enable one, not solving the problem, to predict the composition and structure of glass‐ceramic subsurface layers produced in a certain glassy material and under given ion‐exchange conditions. It was shown that the developed model correctly describes experimental data on ion‐exchange‐induced glass‐ceramics decrystallization. It appears that the model can be used in developing a new technology of optical glass‐ceramics for photonic applications.     

离子交换树脂在纯水制备方面的应用

本文详解了离子交换树脂在纯水制备方面的应用。阐述了用离子交换树脂生产超纯水、高纯水的工艺流程及其特点,综述了离子交换树脂在纯水制备方面的应用现状。     

3种离子交换相平衡模型在Tau/OH~-体系中的比较

在牛磺酸/氢氧根相平衡体系下,对计量置换模型、异质作用模型和改进的Langmuir模型的计算精度等特性进行了比较。采用静态法进行牛磺酸/氢氧根体系的离子交换平衡实验,测定30℃下的离子交换等温线;分别使用计量置换模型、异质作用模型和改进的Langmuir模型方程对相平衡数据进行拟合得到相关模型参数。结果表明:改进的Langmuir模型在一定牛磺酸浓度范围内可以正确地描述Tau/OH-体系的相平衡,拟合结果优于计量置换模型和异质作用模型。     

离子交换对硼硅酸盐平板玻璃表面组成及性能的影响

研究用低温离子交换法增强硼硅酸盐平板玻璃.以熔融KNO3作为离子交换源,分别加入少量KOH,KF和锑酸钾(K2H2Sb2O72H2O)添加剂,在玻璃转变温度以下对硼硅酸盐平板玻璃进行K -Na 离子交换处理.利用电子探针研究了离子交换前后玻璃的表面组成变化;测定了样品的显微硬度、抗折强度和透过率.研究了添加剂种类与玻璃抗折强度之间的关系.研究结果表明:经K -Na 离子交换处理后硼硅酸盐玻璃表面K 浓度增加,交换深度可达30μm.经K -Na 离子交换后硼硅酸盐平板玻璃的强度提高,其抗折强度约为交换前的3倍.     

离子交换法从卤水中提取硼酸

中国很多的盐湖卤水中都富含大量的硼矿资源，从中提取硼酸的方法也有很多，如：酸化结晶法、沉淀法、萃取法、离子交换法等，其中离子交换法被认为是这些方法中最有前途的方法之一。综述了采用离子交换法从含硼盐湖卤水中提取硼酸的工艺原理和影响因素，列出了几种常用的提硼树脂，介绍了应用离子交换法从卤水中提取硼酸的现状。     

连续电再生离子交换原理探讨

连续电再生离子交换系统(EDI)将电渗析技术和离子交换技术结合起来,无需酸、碱再生。其工作原理是系统中阴、阳离子交换树脂对水中离子的吸附交换、在电场作用下离子的定向迁移以及离子交换树脂的平衡再生。     

离子交换树脂复苏方法的应用

阳床离子交换树脂被Fe3＋污染、混床离子交换树脂被有机物和铵污染后,交换能力下降,通过问题分析,利用再生剂进行复苏处理,恢复树脂活性。     

不同分子质量的腐殖酸对溴离子在MIEX树脂上吸附行为的影响

采用静态吸附法研究了不同分子量的腐殖酸对溴离子(Br?)在MIEX树脂上吸附行为的影响. 结果表明,pH为中性时,4种腐殖酸(分子量分别为小于1000, 1000?5000, 5000?10000, 大于10000)使MIEX树脂对Br?的去除率从80.05%分别降至75.39%, 26.32%, 42.67%和49.03%,而酸性(pH<5.0)或碱性(pH>9.0)时,各种腐殖酸则会促进Br?去除,pH为11.0时去除效率增加最明显. 分子量大于10000的腐殖酸可将吸附平衡时间由60 min缩短至20 min,分子质量1000?5000和5000?10000的腐殖酸可将吸附平衡时间缩短至40 min. 但不论有无腐殖酸,MIEX树脂对Br?的吸附过程均符合拟二级反应动力学模型. 不同分子量的腐殖酸均能明显降低Br?在MIEX树脂上的吸附平衡容量,分子量大于10000的腐殖酸影响最大,但均不改变吸附平衡模型类型,吸附平衡规律用Langmuir与Freundlich模型均可很好描述. 不同分子量的腐殖酸对MIEX树脂去除Br?的影响与溶液pH值密切相关,腐殖酸会加速Br?在树脂上的吸附过程,但不改变吸附平衡及动力学模型类型.