Abstract: Contaminating ions are removed from an aqeuous medium, e.g. hexavalent chromium ions from cooling tower waters, by an electrochemical method which includes formation of an insoluble iron compound or complex of the contaminant ion, utilizing an anode of iron, iron alloy or insoluble iron compound. The electrodes are treated with an acid solution at regular intervals to remove any substances formed on or lodged between the electrodes. The electrolytic cell includes a plurality of closely spaced generally parallel plate electrodes with electric potential applied to the two end electrodes, and an electrode near each end electrode is of a size protecting the end electrode from flux field effects.

Abstract: Contaminating ions are removed from an aqueous medium, e.g. hexavalent chromium ions from cooling tower waters, by an electrochemical method which includes formation of an insoluble iron compound or complex of the contaminant ion, utilizing an anode of iron, iron alloy or insoluble iron compound. The electrodes are treated with an acid solution at regular intervals to remove any substances formed on or lodged between the electrodes. The electrolytic cell includes a plurality of closely spaced generally parallel plate electrodes with electric potential applied to the two end electrodes, and an electrode near each end electrode is of a size protecting the end electrode from flux field effects.