Abstract:

 A dielectric measurements were carried out over the frequency range 10~107 Hz for the systems comprising strong, weak charged membranes and solution. A distinct double dielectric relaxation was observed under application of d.c. bias voltage. The data on the double relaxation for cation-exchange membrane were analyzed by using a dielectric theory for concentration polarization layer(CPL), the structure parameters of the layer and phase parameters of the two adjoining aqueous phases were obtained from dielectric parameters observed. The cause of dielectric relaxation was discussed in detail. The results of simulation basis of dielectric theory of CPL made in previous study are shown to be reasonable, and a high possibility in respect to the origin of the dielectric relaxation was suggested by the experiments.

Key words: Concentration polarization, Dielectric relaxation, Ion-exchenge membrane