scispace - formally typeset
Search or ask a question
Journal ArticleDOI

Mobility and self-diffusion coefficient of sulphate co-ion in a grafted cation-exchange membrane

01 Jul 1987-Journal of Membrane Science (Elsevier)-Vol. 32, pp 175-184
TL;DR: In this paper, the authors used 0.001-0.50 M MgSO 4 as external electrolyte to calculate the self-diffusion coefficient and mobility of the sulphate co-ion in polystyrene grafted onto a polyethylene membrane.
About: This article is published in Journal of Membrane Science.The article was published on 1987-07-01. It has received 3 citations till now. The article focuses on the topics: Membrane & ITIES.
Citations
More filters
Journal ArticleDOI
TL;DR: In this article, the surface charge of commercial nanofiltration (NF) membranes through streaming potential measurements was determined by using the Gouy-Chapman equation, and the results showed a logarithmic relationship between the membrane surface charge and the feed solution concentration.

202 citations

Journal ArticleDOI
TL;DR: In this paper, the effect of salt concentration and pH on the surface charge of loose nanofiltration (NF) membranes through streaming potential measurements was studied, where a Dow pilot unit equipped with a plate-and-frame module allowed the simultaneous test of two commercial NF membranes: Celgard N30F and Celgard NF-PES-10.

66 citations

Journal ArticleDOI
TL;DR: In this article, the co-ion fluxes and the influence of operating parameters were studied and it was shown that a more than linear increase in co-ions flux with respect to the ion concentration was observed.

33 citations


Cites background from "Mobility and self-diffusion coeffic..."

  • ...Chakravarti studied the mobility and self-diffusion coefficient of the sulphate co-ion in a grafted cation-exchange membrane [16]....

    [...]

  • ...The quantity of counter and co-ions in ion-exchange membranes has been widely studied in the literature [8, 13-17]....

    [...]

References
More filters
Journal ArticleDOI
TL;DR: An equation for the flux of electrolyte through a water-swollen cation-exchange resin membrane separating two solutions of the same electrolyte at different concentrations is derived on the basis of several assumptions regarding the physical nature of a swollen resinous exchanger.
Abstract: An equation for the flux of electrolyte through a water-swollen cation-exchange resin membrane separating two solutions of the same electrolyte at different concentrations is derived on the basis of several assumptions regarding the physical nature of a swollen resinous exchanger. The complete flux equation contains three terms, one determined by the concentration difference across the membrane, another determined by the variation of the activity coefficient of the electrolyte with concentration in the membrane and a third concerned with the rate of osmotic or hydrostatic flow through the membrane. If ions in the resin are transported entirely in an internal aqueous phase, the mobilities required for the flux equation can be related to mobilities in aqueous solution and to the volume fraction of resin in the swollen membrane. The treatment is readily extended to anion exchangers.

476 citations

Journal ArticleDOI
TL;DR: In this paper, the flux equations of part I have been tested for the diffusion of five salts at three temperatures through a Zeo-Karb disk, and the results support the main tenet of the theory that transport of ions in the resin takes place in an internal aqueous phase.
Abstract: The flux equations of part I have been tested for the diffusion of five salts at three temperatures through a Zeo-Karb disk. The experiments were carried out using a vitreous silica apparatus working on a constant-flow principle. The data support the main tenet of the theory that transport of ions in the resin takes place in an internal aqueous phase. A fair quantitative agreement is obtained. The theory would be improved by taking into account counterion binding by the resin and the electrophoretic effect in diffusion.

105 citations

Journal ArticleDOI
TL;DR: In this article, a hole scavenging experiment was attempted by adding azide ion; however, no significant enhancement of anodic photocurrents was observed in a 10 mM solution of NaN3 in DMF.
Abstract: potentials, and removal of the N20 by A.r bubbling reduces them, thus indicating the presence of some photoelectron emission. Protons are not useful scavengers in nonaqueous media because proton reduction severely limits the accessible potential range. An analogous hole scavenging experiment was attempted by adding azide ion; N3oxidizes irreversibly to NP. However, no significant enhancement of anodic photocurrents was observed in a 10 mM solution of NaN3 in DMF. One can surmise that the surface concentration of azide ion was too low to compete with water or other electron scavengers a t the electrode surface. It is probable that strong adsorption of azide is necessary to obtain a sufficiently high concentration for effective hole scavenging. References and Notes

85 citations

Journal ArticleDOI
TL;DR: In this article, the observed abnormal behavior of the electrolyte uptake in ion exchangers is interpreted quantitatively on the basis of a widespread non-uniformity of distribution of the counter-ions.
Abstract: The observed abnormal behaviour of the electrolyte uptake in ion exchangers (see preceding paper by Glueckauf & Watts) is interpreted quantitatively on the basis of a widespread non-uniformity of distribution of the counter-ions. In the case fully treated in this paper, i.e. for an exchanger of mean molality of 4.17, the range of counter-ion concentrations is shown to extend from about 15 molal to 10$^{-4}$ molal. This non-uniformity must have significant effects on the variation of the ion exchange separation factor at different mol-fractions in the exchanger phase. It explains qualitatively the observed fact, that the separation factor is usually larger when the more strongly sorbed ion is present at low mol-fractions, and that this effect increases both with the mean molality of the exchanger, and with the magnitude of the separation factor. The wide non-uniformity also explains the observed variation of the diffusion coefficient of imbibed electrolyte with concentration. A new quantitative treatment is introduced for diffusion through widely non-uniform media. Full agreement between theory and experiment is obtained at high uptake concentrations. At low uptake concentrations, two curves are obtained from the theory, according to whether the low concentration regions in the exchanger are considered as \`continuous' or \`disperse'. The observed data lying between these two calculated curves suggest a considerable \`continuity' for the low concentration regions. They indicate the existence of a \`continuous' network of submicroscopic aqueous fissures or channels of about 70 $\overset{\circ}{\mathrm A}$ width, widening occasionally to as much as 2000 $\overset{\circ}{\mathrm A}$. The resulting electrical double layer effects in these fissures explain the wide continuous variation of counter-ion concentrations.

71 citations