Transport of Current during Fractionation by Electrodialysis through Ion-exchange Membranes

Abstract

IN most experimental arrangements for electrodialysis using ion-exchange membranes, the ions of the electrolyte after being transported through the membranes are either discharged directly at the electrodes or recombine and neutralize each other's charge in an adjoining compartment. Thus, in industrial equipment for desalting brackish water, alternating cation- and anion-permeable membranes form a number of compartments between the electrodes. The saline water to be desalted is passed through every other compartment, and the ions from this water, after electrodialysis through the membranes, recombine in the remaining compartments to give a concentrated salt solution which is then discharged to waste¹.