NACL DIFFUSION ACROSS AN AMPHOTERIC ION-EXCHANGE MEMBRANE

The diffusion of NaCl across an amphoteric ion exchange membrane has been studied by measuring the diffusion flux of NaCl and the self-diffusion fluxes of Na+ and Cl- ions through this membrane. The NaCl fluxes through the amphoteric membrane are analysed on the basis of the Nernst-Planck equation and the TMS theory. The self-diffusion measurements make possible calculations of the individual diffusion coefficients. The effects of the external pH on the physicochemical properties of the membrane are discussed. The measurement of the NaCl content in the membrane combined with the result of the membrane potential and with the result of the self diffusion measurements make it possible to obtain the theoretical values of the NaCl flux. These values are in satisfactory agreement with the experimental values.