An electrodeionization (EDI) apparatus and method comprising an
ion-depleting chamber for removing ions from liquids passed therethrough,
wherein a resistive component is coupled proximate the outlet region of
the chamber so as to increase the electrical resistance of the outlet
region of the chamber with respect to the inlet region of the chamber.
The resistive component may be coupled to the ion-selective membranes
bordering the diluting chamber and/or the concentrate chambers. In an
alternative embodiment, the resistive component may be coupled between
the ion-exchanging media particles themselves within the ion-depleting
chambers. In each embodiment, the electrical resistance of the outlet
region is increased with respect to the inlet region of the chamber, with
results being that electrical current is shifted from the outlet region
toward the inlet region, thus enhancing overall deionization performance
of the EDI device.