MASS-TRANSPORT ENHANCEMENT IN THE ELECTRODIALYSIS OF DILUTE-SOLUTIONS

Possibilities for enhancing mass transport at the ion-exchange membran e/solution interface were analyzed. Data which were obtained when inve stigating membrane systems by voltammetry and laser interferometry, as well as data for the modulus of impedance, heat evolution, and transp ort numbers which were obtained as functions of current density, were generalized. It was shown that transport through the membranes can be enhanced substantially when working with supralimiting currents. It wa s found that mass transport increases with increasing ratios i/i(lim). The effect of supralimiting current operation in the electrodialysis of dilute solutions was confirmed in the instance of deionization of t ap water and of the rinsing liquors of plating shops.