The permselectivity of membrane systems with an inhomogeneous distribution of fixed charge groups
- Royal Inst. of Technology, Stockholm (Sweden). Dept. of Hydromechanics
- Univ. de Valencia, Burjassot (Spain). Dept. de Termodinamica
The influence of the inhomogeneities in the fixed charge distribution on the transport properties (permselectivity and current-voltage characteristics) of ion-exchange membranes is theoretically studied. A simple, approximate method for the analytical solution of the Nernst-Planck equations with the assumption of local electroneutrality is presented. Special attention is paid to the effect of the diffusion boundary layers on the permselectivity of the membrane system. Two fixed charge distributions (linear and exponential) are considered in detail. It is predicted that these distributions could show higher permselectivities than a homogeneous distribution with the same average concentration. Still, the membrane permselectivity is mainly determined by the average fixed charge concentration and the thickness of the boundary layers.
- OSTI ID:
- 6819156
- Journal Information:
- Journal of Colloid and Interface Science; (United States), Vol. 168:1; ISSN 0021-9797
- Country of Publication:
- United States
- Language:
- English
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