Reduction of polarization in electrodialysis by ion-conducting spacers

Abstract A new method to decrease polarization in electrodialysis is suggested, with the aid of ion-conducting spacers. Spacers were prepared and tested. It was found that high current efficiency can be preserved at high current densities, in the present experiments up to 30 mA/cm2 for a 0.011 N dialysate. Resistance of the dialysate compartment was lower than that corresponding to a homogeneous layer of solution for dilute dialysates. An open stack design made possible by the spacer is discussed.