Decolorization of synthetic Methyl Orange wastewater by electrocoagulation with periodic reversal of electrodes and optimization by RSM

摘要: Abstract Treatment of Methyl Orange (MO), an azo dye, synthetic wastewater by electrocoagulation with periodic reversal the electrodes (PREC) was examined. Response Surface Methodology (RSM) used to optimize influence experimental conditions for color removal (CR), energy consumption (ENC), electrode (ELC) and sludge production (SP) per kg MO removed (kg(MOr)) optimal being found be pH 7.4, solution conductivity (к) 9.4 mS cm−1, cell voltage (U) 4.4 V, current density (j) 185 mA cm−2, time (T) 14 min, cycle (t) 15 s, inter-electrode distance (d) 3.5 cm initial concentration 125 mg L−1. Under these conditions, 97 ± 2% ENC, ELC SP were 44 ± 3 kWh kg(MOr)−1, 4.1 ± 0.2 kg(Al) kg(MOr)−1 17.2 ± 0.9 kg(sludge) kg(MOr)−1, respectively. With enhanced electrochemical efficiency resulting from reversal, coefficients increased resistance decreased between two in PREC setup 2.48 × 10−4 Ω cm−2 min−1 0.29 mA cm−2 min−1, respectively, as compared 7.72 × 10−4 Ω cm−2 min−1 0.79 mA cm−2 min−1 measured traditional process. The rate constant decolorization also 20.4% 0.152 min−1 process 0.183 min−1 These performance characteristics indicate that approach may more promising terms practical application, a cost-effective treatment, than conventional textile dye removals.