Applications Of Ion-exchange Membranes Research Articles

Recent Patented Applications of Ion-Exchange Membranes in the Agrifood Sector

Recent Patented Applications of Ion-Exchange Membranes in the Agrifood Sector

Preparation and characterization of a cation exchange membrane using a styrene-hydroxyethyl acrylate-lauryl methacrylate terpolymer

A novel cation exchange membrane based on a styrene-hydroxyethyl acrylate-lauryl methacrylate terpolymer (St-HEA-LMA) was prepared. Sulfonic groups were introduced to the membrane structure with sulfuric acid as the sulfonating agent and silver sulfate as the initiator. Sulfonated St-HEA-LMA terpolymer membranes were characterized by Fourier-transform infrared (FTIR) spectroscopy and atomic force microscopy (AFM), as well as by determining the degree of sulfonation (DS), ion-exchange capacity (IEC), swelling ratio and electrical resistance of the membranes. The presence of sulfonic groups in the sulfonated St-HEA-LMA terpolymer was confirmed by FTIR, and the resulting membrane exhibited an ion-exchange capacity of 2.13 meq/g and an electrical resistance of 1.17 Ω·cm2. The swelling ratio of the prepared membranes increased with increasing degree of sulfonation, and the tensile strength decreased with increasing degree of sulfonation at a reaction temperature of 30°C. The phase images obtained by AFM clearly showed an increase in roughness with increasing DS. Considering the mechanical properties, the sulfonated St-HEA-LMA terpolymer obtained at a sulfonation reaction temperature of 20°C was suitable for ion-exchange membrane applications.

Modeling the ion transfer and polarization of ion exchange membranes in bioelectrochemical systems

An explicit numerical model for the charge balancing ion transfer across monopolar ion exchange membranes under conditions of bioelectrochemical systems is presented. Diffusion and migration equations have been solved according to the Nernst–Planck Equation and the resulting ion concentrations, pH values and the resistance values of the membrane for different conditions were computed. The modeling results underline the principle limitations of the application of ion exchange membranes in biological fuel cells and electrolyzers, caused by the inherent occurrence of a pH-gradient between anode and cathode compartment, and an increased ohmic membrane resistance at decreasing electrolyte concentrations. Finally, the physical and numerical limitations of the model are discussed.

Characterization of ion-exchange membrane materials: Properties vs structure

This review focuses on the preparation, structure and applications of ion-exchange membranes formed from various materials and exhibiting various functions (electrodialytic, perfluorinated sulphocation-exchange and novel laboratory-tested membranes). A number of experimental techniques for measuring electrotransport properties as well as the general procedure for membrane testing are also described. The review emphasizes the relationships between membrane structures, physical and chemical properties and mechanisms of electrochemical processes that occur in charged membrane materials. The water content in membranes is considered to be a key factor in the ion and water transfer and in polarization processes in electromembrane systems. We suggest the theoretical approach, which makes it possible to model and characterize the electrochemical properties of heterogeneous membranes using several transport-structural parameters. These parameters are extracted from the experimental dependences of specific electroconductivity and diffusion permeability on concentration. The review covers the most significant experimental and theoretical research on ion-exchange membranes that have been carried out in the Membrane Materials Laboratory of the Kuban State University. These results have been discussed at the conferences “Membrane Electrochemistry”, Krasnodar, Russia for many years and were published mainly in Russian scientific sources.

Application of Ion-Exchange Membranes for Stabilizing Acidity of a Chromium-Plating Electrolyte Based on Chromium(III) Sulfate

The acidity of a chromium-plating electrolyte based on chromic sulfate may be stabilized in a two-chamber electrolyzer with an anion-exchange membrane (AEM). The optimum concentration of sulfuric acid in the anolyte (c sa) may be selected on the basis of the material balance equation for the catholyte, which allows for the dependence of the transport number of hydronium ions in AEM on c sa. No considerable accumulation of Cr2+ occurs in the catholyte during a prolonged electrolysis. The transport of formate ions through AEM at working values of electrolyte pH is inconsiderable.

Preparation and applications of ion exchange membranes by radiation-induced graft copolymerization of polar monomers onto non-polar films

Preparation and applications of ion exchange membranes by radiation-induced graft copolymerization of polar monomers onto non-polar films

Electro-organic synthesis without supporting electrolyte: Possibilities of solid polymer electrolyte technology

The application of ion exchange membranes as solid polymer electrolytes (SPE) in fuel cells is state-of-the-art. This technology needs no supporting electrolyte; consequently it can be applied for electro-organic syntheses in order to save process steps. In this case the process is not predetermined to a maximized energy efficiency so that the selection of the cell design, of the electrode materials and of the operating conditions can be focused on a high selectivity of the electrode reactions. The electro-osmotic stream, which is caused by the solvation shells of the ions during their migration through the membrane, and hence is a typical property of SPE technology, has a significant effect on the electrode reactions. It generates enhanced mass transfer at the electrodes, which is beneficial for reaction selectivity. It can be influenced by the choice of, and possibly by the preparation of, the membrane. An additional remarkable advantage of SPE technology is the exceptional long durability of oxide coated electrodes. By combination of several process engineering methods stable operation of SPE cells has been realized, even for examples of non-aqueous reaction systems. Experiments up to 6000 h duration and in cells of up to 250 cm2 membrane area show the potential for industrial application.

Neurotic disorders: Stress and immunity

This review focuses on the preparation, structure and applications of ion-exchange membranes formed from various materials and exhibiting various functions (electrodialytic, perfluorinated sulphocation-exchange and novel laboratory-tested membranes). A number of experimental techniques for measuring electrotransport properties as well as the general procedure for membrane testing are also described. The review emphasizes the relationships between membrane structures, physical and chemical properties and mechanisms of electrochemical processes that occur in charged membrane materials. The water content in membranes is considered to be a key factor in the ion and water transfer and in polarization processes in electromembrane systems. We suggest the theoretical approach, which makes it possible to model and characterize the electrochemical properties of heterogeneous membranes using several transport-structural parameters. These parameters are extracted from the experimental dependences of specific electroconductivity and diffusion permeability on concentration.The review covers the most significant experimental and theoretical research on ion-exchange membranes that have been carried out in the Membrane Materials Laboratory of the Kuban State University. These results have been discussed at the conferences “Membrane Electrochemistry”, Krasnodar, Russia for many years and were published mainly in Russian scientific sources.

Thermodynamic interpretation of polyionic membrane cell emf's in terms of mixed electrolytes activities

Many applications of ion-exchange membranes involve polyionic transfers between multicomponent electrolyte solutions. Polyionic membrane cell potentials are usually interpreted in terms of individual ionic activities, i.e. nonthermodynamic, conventionally established quantities. A new, complete scheme is here described for evaluating emf's of polyionic membrane cells in terms of thermodynamic mean ionic activities in mixed electrolytes together with the relevant ion and solvent transference numbers. Applications of the proposed scheme are described for (a) the determination of transference numbers of ions and solvent across membrane, and (b) the determination of selectivities of membranes to be used in ion-selective electrodes.

Application of ion exchange membranes in the plating industry

Application of ion exchange membranes in the plating industry

Application of ion exchange membranes to the recovery of acids by diffusion dialysis

The optimum operating conditions for diffusion dialysis were studied for the recovery of nitric acid and hydrofluoric acid from mixed solutions containing these acids and ferric ions. Nitric acid was recovered for more than 100% and hydrofluoric acid for 50-60%. Ferric ion was eliminated for 85 to 90%.

Application of ion exchange membranes to sampling and enrichment. Interference of metal ion binding groups

Application of ion exchange membranes to sampling and enrichment. Interference of metal ion binding groups

Some Applications of Ion Exchange Membranes in Automatic Coulometric Aqueous Acid-Base Titrations.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSome Applications of Ion Exchange Membranes in Automatic Coulometric Aqueous Acid-Base Titrations.P. P. L. Ho and M. M. MarshCite this: Anal. Chem. 1963, 35, 6, 618–620Publication Date (Print):May 1, 1963Publication History Published online1 May 2002Published inissue 1 May 1963https://doi.org/10.1021/ac60199a037RIGHTS & PERMISSIONSArticle Views42Altmetric-Citations10LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (373 KB) Get e-Alerts Get e-Alerts