Alternating Current for the Selective Electrodeposition of Cadmium, Iron, and Chromium Method Development for Simulated Industrial Wastewater Sludge

Abstract

A preliminary study of the selective electrodeposition of Cadmium (Cd), Iron (Fe), and Chromium (Cr) from industrial wastewater sludge using alternating current. There are no large-scale methods for recovering the metals contained in the sludge resulting from industrial wastewater treatment. This study expanded on a method for using Alternating Current (AC) and a Graphene-Oxide-Modified Carbon Felt Electrode (CF-GO) by using a larger volume than previously used in literature and optimizing AC settings for the selected metals. Cd concentration in solution was reduced by 5-10% over five hours using an AC setting of 4 MHz, 2 Vpp, and -5 VOffset. Fe had five AC settings that had regression line slopes less than -4 ppm/ hr, and Cr had one AC setting with regression line slope less than -4 ppm/hr. As the Cr AC setting of 1 Hz, 1 Vpp, and -8 VOffset also was efficient for the electrodeposition of Fe, the Fe would need to be removed from solution before Cr. Future work outlined includes further AC optimization, additional metals also found in industrial wastewater sludge, optimization of the order of metals electrodeposited, and testing the method on industrial wastewater sludge.