Self-diffusion of water and fluorine ions in anion-exchange polymeric materials (membranes and resin) as determined by pulsed-field gradient nuclear magnetic resonance spectroscopy
Date
2000
Authors
Volkov V.I.
Popkov Yu.M.
Timashev S.F.
Bessarabov D.G.
Sanderson R.D.
Twardowski Z.
Journal Title
Journal ISSN
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Abstract
The self-diffusion of water, ethanol and fluorine ions was studied by means of pulsed-field gradient nuclear magnetic resonance (PFG-NMR) spectroscopy in anion-exchange materials such as membranes and a resin containing quaternary amines as functional groups. Measurements were carried out with a NMR spectrometer at a frequency of 100MHz for 1H and 94.3MHz for 19F. The temperature dependence of the diffusion decay components in F- form membranes equilibrated with water or an aqueous solution of NH4FxHF was studied. The morphology of the transport channels in these materials and relationship between the structure of the membrane transport channels and self-diffusion of water and F- ions have been discussed. It was shown that the values of self-diffusion of fluorine ions in the membranes as determined by PFG-NMR are in good agreement with those obtained by means of electroconductivity measurements. Copyright (C) 2000 Elsevier Science B.V.The self-diffusion of water, ethanol and fluorine ions was studied by means of pulsed-field gradient nuclear magnetic resonance (PFG-NMR) spectroscopy in anion-exchange materials such as membranes and a resin containing quaternary amines as functional groups. Measurements were carried out with a NMR spectrometer at a frequency of 100 MHz for 1H and 94.3 MHz for 19F. The temperature dependence of the diffusion decay components in F- form membranes equilibrated with water or an aqueous solution of NH4F×HF was studied. The morphology of the transport channels in these materials and relationship between the structure of the membrane transport channels and self-diffusion of water and F- ions have been discussed. It was shown that the values of self-diffusion of fluorine ions in the membranes as determined by PFG-NMR are in good agreement with those obtained by means of electroconductivity measurements.
Description
Keywords
Diffusion, Ethanol, Fluorine, Nuclear magnetic resonance spectroscopy, Polymeric membranes, Resins, Thermal effects, Water, Diffusion decay, Ion exchange resins, amine, ammonium fluoride, anion exchange resin, fluorine, functional group, hydrofluoric acid, ion, polymer, water, diffusion, fluorine, ion exchange, nuclear resonance spectroscopy, polymer, water, anion exchange, aqueous solution, article, controlled study, diffusion, diffusion coefficient, membrane, membrane transport, morphology, nuclear magnetic resonance spectroscopy, priority journal, proton nuclear magnetic resonance, pulsed field gradient, temperature
Citation
Journal of Membrane Science
180
1
180
1