Optimization of operational parameters using central composite design in the peroxi-alternating current-electrocoagulation process for the pollutant removal with determination of power consumption from industrial wastewater

Abstract

The utilization of electrochemical and advanced oxidation technologies for industrial wastewater (IW) treatment has grown in popularity during the last two decades. The effectiveness of several methods for treating IW, includ ing hydrogen peroxide (H2O2), direct-current (DC) and alternating-current (AC)-electrocoagulation (EC), and the combination of H2O2 with DC/AC-EC (H2O2-DC/AC-EC) processes were all investigated. In comparison to the H2O2, DC/AC-EC, and H2O2-DC/AC-EC technologies, the results showed that the H2O2-AC-EC process produced 100% total colour and 100% chemical oxy gen demand (COD) removal efficiency with a low power consumption of 4.4 kWhm−3.TheH2O2/AC-EC technology was optimized for treating IW using a response surface methodology approach based on a central composite design using a five-factor level. Utilizing statistical and mathematical techniques, the optimum parameters were determined to minimize consumption of power (1.02 kWhm−3)andmaximumCODelimination(75%). The experimental parameters comprised the following: H2O2 of 600 mg/L, current of 0.65 Amp, pH of 7.6, CODof1600 mg/L, and treatment time (TT) of 1.26 h. When using a Fe/Fe elec trode combination with the wastewater pHof 7,the CODremovalefficiencywas shown to be enhanced by increasing the TT, current and H2O2, and decreas ing the COD concentration. The synergistic impact, quantified as the combined efficiency of eliminating % COD utilizing the H2O2, AC-EC, and H2O2/AC-EC