In this work, MCDI performance was correlated to ion-exchange membrane thickness. The experimental design evaluated examined:
i.) commercially available ion-exchange membranes, ii.) ion-exchange layered electrodes of different thicknesses with electrode samples being prepared by drop casting followed by spray painting of ionomer layer on top of the electrode; and iii.) drop casting a mixture of electron conducting carbon with dissolved ionomer. A home-built, single-cell MCDI module was characterized with the different ion-exchange materials using a 275 ppm salt feed. MCDI performance was determined by quantifying salt removal and energy efficiency and the individual resistance contributions in the system through electrochemical impedance spectroscopy.
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