Performance of electrocoagulation for food azo dyes treatment in aqueous solution: optimization, kinetics, isotherms, thermodynamic study and mechanisms
Marwa Bendaia, Sabir Hazourli, Adel Aitbara, Nait Merzoug Nesrine
Abstract
Electrocoagulation process was applied for the removal of Acid Red 14 in bath essays. Under optimal operating conditions: current density of 70 mA/cm2, 60–90 min of reaction, natural pH, and an initial concentration of 50 mg/L, the decolorization and COD removal efficiencies were 95% and 90%, respectively. The electrical energy consumption was 110 kWh/kgAR.14removed. These experimental results are well modeled by the Langmuir and Freundlich isotherms and follow first-order reaction kinetics. The thermodynamic parameters indicated that the nature of the adsorption process was endothermic and spontaneous. The mud formed after electrocoagulation was characterized by FTIR and SEM coupled to EDS.