Energy efficient electrocoagulation using brass electrode for simultaneous nickel and chromium removal from synthetic wastewater: Cost and parametric evaluation

Electrocoagulation process using brass anode was designed for simultaneous removal of nickel (Ni) and chromium (Cr (VI)) from synthetic wastewater. In the present work, the effect of current density (Cd) 13.16–65.79 A/m2, the concentration of chromium (CC) and nickel (CN): 10–50 mg/L, pH: 2–10, Electrode distance (Ed): 0.7–3.5 cm, types of electrode material, and supporting electrolyte have been studied on the nickel and chromium removal. The brass electrode demonstrated Cr(VI) and Ni removal percentages of 99.9 % and 99.38 % respectively at concentration of Cr(VI) = Ni = 50 mg/L, Cd = 65.79 A/m2, Ed = 0.7 cm, EC time = 50 min at the initial pH of synthetic wastewater. In addition, the brass electrode demonstrated better performance with lower energy consumption (21.58 kWh/m3) and less operation cost 1.797 US$/m3) as compared to Al, Fe and Cu electrode materials. •Brass electrode introduced for Cr(VI) and Ni removal and found very effective.•Brass electrode demonstrated as an energy efficient electrode as compared to Cu, Fe, and Al electrode.•The effect of electrolytes were negligible on Cr(VI) and Ni removal efficiency.•Increase of electrode distance decreased Cr(VI) and Ni percentage.