离子交换纤维

本文介绍了离子交换纤维的三种主要制备方法以及离子交换纤维在作分离纯化过滤材料和分析用离子交换柱填充剂等方面的用途.     

聚丙烯离子交换纤维研究

利用超声波分散原理将苯乙烯（St）分散到聚丙烯纤维（PP）中，以过氧化苯甲酰（BPO）作为引发剂，使苯乙烯接枝到PP纤维表面，得到PP－g-St纤维；然后用浓硫酸将PP－g-St纤维磺化，制成强酸型离子交换纤维。研究了反应时间、反应温度等对离子交换纤维的质量摩尔浓度的影响，并用红外光谱加以表征。结果表明：温度90℃下磺化反应2h，可得到离子交换质量摩尔浓度为0.95mmol/g的强酸型离子交换纤维。     

离子交换纤维的应用与展望

详细介绍了离子交换纤维的应用现状，并展望了其未来的发展方向。     

离子交换纤维的制备与性能研究现状

阐述了离子交换的发展历史以及目前各国在此领域的主要成就，介绍了离子交换纤维的结构特点，重点介绍了各种离子交换纤维的制备方法及其物理化学性能。     

离子交换纤维吸附偏二甲肼的性能

研究了强酸性离子交换纤维对偏二甲肼的吸附、解吸性能。静态吸附结果表明,反应温度对纤维的吸附效果有影响。动态吸附、解吸结果表明,纤维在离子交换柱中的装填密度、原液的浓度、流速对吸附效果有影响,用少量的氯化钠溶液可将吸附的偏二甲肼迅速解吸下来,并且使解吸液浓缩倍数达28.3倍。     

离子交换纤维吸附儿茶素的热力学

采用自制离子交换纤维对儿茶素的吸附特性进行了研究,在温度为286～328 K和研究的浓度范围内,离子交换纤维对儿茶素吸附平衡数据符合Langmuir和Freundlich吸附等温方程.Freundlich吸附等温线和等量吸附焓表明：离子交换纤维对儿茶素吸附是吸热过程.对儿茶素在离子交换纤维上的吸附焓、自由能、吸附熵的计算表明,该离子交换纤维对儿茶素的吸附没有化学键生成,并对吸附行为作了合理解释.     

离子交换纤维在污水处理中的应用

离子交换纤维是一种新型的功能纤维材料,能够有效地吸附污水中的重金属离子。介绍了离子交换纤维吸附重金属离子的原理、性能特点、应用和发展趋势。     

离子交换纤维吸附偏二甲肼的热力学研究

对自制强酸性离子交换纤维吸附偏二甲肼的特性进行了研究,在温度为287~318 K和40~190 mg.L-1的浓度范围内,离子交换纤维对偏二甲肼的吸附符合Langmuir和Freundlich等温吸附方程。不同温度下等温吸附曲线的测定和等量吸附焓的计算表明:离子交换纤维对偏二甲肼的吸附是吸热过程。对偏二甲肼在离子交换纤维上的吸附焓、吉布斯自由能、吸附熵的计算表明,该离子交换纤维对偏二甲肼的吸附没有化学键生成,并对吸附行为作了合理的解释。     

离子交换纤维在水处理中的应用研究

在研究当前相关文献资料的基础上,结合离子交换纤维表面吸附和分离功能的特点,分别对其在水处理中应用、材料制备和应用现状进行了论述。     

离子交换纤维法去除碱性废水中硫氰酸根的研究

研究了离子交换纤维去除碱性废水中SCN-的可能性,考察了纤维用量、反应时间、初始pH、温度等因素对废水中SCN-去除率的影响,并研究了SCN-的交换等温线。结果表明,强碱性离子交换纤维可有效实现对碱性废水中SCN-的去除,其最佳条件是:反应时间为5 min,反应初始pH为8～11,温度为30℃,在此条件下,SCN-的去除率可达99.5%左右。离子交换纤维去除碱性废水中SCN-的过程受温度影响较大,且满足Boyd液膜扩散公式和Freundlish等温式。     

DUAL-TEMPERATURE ION EXCHANGE FRACTIONATION

ABSTRACT

This paper reviews the results obtained by studying the dual-temperature ion-exchange fractionation (DTIXF) technique. The DTIXF is based on the use of different affinity at different temperatures of ion exchangers towards ions to be separated. This technique allows to design absolutely reagentless and, as a result, wasteless fractionation technology. The review considers the temperature dependencies of selectivity of commercially available ion-exchange (LX) resins towards components of ionic mixtures of different complexity starting from binary model systems up to naturally existing nonacomponent effluents. A novel approach for predicting the temperature sensitivity of a given LX system is presented and discussed. The same approach has been shown to be applicable for the design of IX resins with temperature-dependent selectivity. The paper also reports the results obtained in the practical application of DTIXF technique for concentration of magnesium from seawater and copper from acidic mine waters. The flowsheets of DTLXF processes are proposed and discussed.     

离子交换法提取D-对羟基苯甘氨酸

研究了离子交换树脂提取 D-对羟基苯甘氨酸的方法 ,包括树脂的筛选 ,吸附条件和洗脱条件的确定。     

KINETICS OF CADMIUM ION SORPTION ON ION EXCHANGE AND CHELATING RESINS

ABSTRACT

Cadmium sorption from aqueous solutions on sulfonic (C-150) and iminodiacetic (S-930) Purolite macroporous resins was investigated. The influence of operating variables such as initial pH, Cd(H) concentration, time and temperature on the equilibrium parameters was measured. The ion preference and sorption ability of resins, i.e. binding constant (b) and saturation capacity {x_m), derived from sorption isotherm, depend on the functional group structure. The Cd(II) uptake is only particle diffusion controlled. The kinetic parameters, i.e. t_1/2 values for 50 % attainment of equilibrium sorption, rate constant (K¯ ) and diffusion coefficient (D¯) are higher on the sulfonic resin. The “moving boundary” particle diffusion model fits the entire ion sorption process on chelating resin, but only the initial sorption on the sulfonic resin, confirming the difference in chemistry between chelation and ion exchange.     

SYNTHETIC INORGANIC ION EXCHANGE MATERIALS. XLIII. ION EXCHANGE MECHANISM OF LITHIUM IONS ON CUBIC TANTALIC ACID

ABSTRACT

Ion exchange reaction of lithium ions on cubic tantalic acid (C-TaA) was studied on the basis of pH titration curve for Li+ at 30, 45 and 60°C. The selectivity coefficients were plotted against equivalent fraction of lithium ions in the exchanger at a given temperature, which refers to the Kielland plot The selectivity coefficient on C-TaA was independent of the equivalent fraction of lithium ions in the exchanger up to a certain point and then decreased rapidly due to a phase transition. The results indicate that the reaction was preceded by an ion exchange mechanism for early stage and then phase transition to the hexagonal system.     

新型异相离子交换膜的开发

本就上海化工厂新型膜的开发作一概述。给出了３３６３、３３６４和３３６５异相膜的测试数据。目前该厂离子交换膜的年产量已达３．８×１０＾５ｍ＾２。     

离子交换法精制肝素的研究

采用强碱性Ⅰ型阴离子交换树脂Ｄ２５４与强碱性Ⅱ型阴离子交换树脂Ｄ２０２进行了动态流程精制肝素的比较性研究。实验证明：树脂Ｄ２５３精制肝素的抗凝胶价为１５５ｕ／ｍｇ,效价回收率灰９７％,明显优于树脂Ｄ２０２精制的肝素。对树脂Ｄ２５４精制肝素过程中的一些影响因素作了理论分析。     

ION EXCHANGE PROPERTIES OF THE SULFUR-MODIFIED BIOTITE

ABSTRACT

The ion exchange behavior of a sulfur-modified biotite towards Pb²⁺, Hg²⁺, Co²⁺, Cu²⁺, Cd²⁺ and Zn²⁺ ions has been studied. The ion exchange isotherms of divalent cations were determined and concentration equilibrium constants as a function of metal loading were analyzed. Sulfur modified biotite exhibits high affinity for Hg²⁺, Pb²⁺, Cu²⁺ and Cd²⁺ ions in individual solutions and in the presence of electrolytes. About 200 mg Hg/g uptake in 1·10^?3 M Hg²⁺ solution and ～ 35 mg Hg/g in groundwater simulant or an alkaline simulant 2 M in NaN0₃ + 1 M in NaOH was found. The possibility of a complex ion exchange and precipitation mechanism of the sulfur modified biotite towards the soft cations is proposed.     

离子交换选择性系数测定

本文叙述了离子交换选择性系数的测定原理、测定方法以及试验体系的设计；实测了强酸阳树脂RH—Na、RNa—Ca和RH—Ca交换体系的选择性系数，并对不同条件时选择性系数的规律性作了初步探讨，得出了不同条件时选择性系数的一般规律。