SALT TRANSPORT IN STRUCTURALLY INHOMOGENEOUS ION-EXCHANGE MEMBRANES

The problem of mass and charge transport in ion-exchange membranes was solved while allowing for their inhomogeneity. The method used does not require the interpretation of models for membrane material structure. The power-law dependence of membrane conductivity and diffusion fluxes on solution concentration was used in finding the concentration dependence of the electrodiffusion coefficients. The concentration dependence of the kinetic parameters was discussed for the best-known membranes MK-40 and MA-40. The counterion and coion fluxes were examined as functions of current and membrane thickness. The shape of the concentration profiles in the membranes was analyzed as afunction of direction and value of the current flowing through the membrane.