Abstract
Impedance measurements of a bed of Na-type cationic ion-exchange resins packed between two platinum electrodes were carried out under a flow of highly purified water. The high frequency region reflected a charge-discharge process, which changed into a diffusion-limiting process at about 600 Hz, and a discontinuous change with hysteresis in the Cole-Cole plot was observed in a lower frequency. Detailed experiments showed that the frequency of the discontinuity depends on the days that passed before the measurement. As hysteresis is a cooperative phenomenon being strongly associated with a positive feedback mechanism, it is important to investigate water dissociation from the viewpoint of nonequilibrium systems.
