Electrochemical Treatment of Industrial Effluent and Its Impact on Stainless Steel Corrosion

Abstract

Controlling environmental problems and treating wastewater are major concerns. In the last decade, electrochemical coagulation has arose as the most effective wastewater treatment process when compared to traditional wastewater treatment techniques. A laboratory scale electrocoagulation (EC) process was used in this study to treat industrial dye effluent via ongoing anodic dissolution of stainless steel anode for artificially aerated galvanic cells. To achieve the highest possible treatment efficiency, two essential parameters such as treatment time (15, 30, 45, and 60 min) and applied potential (400, 750, 900, 1200 mV) was assessed. To verify the effectiveness of the purification method, physicochemical analysis, ultraviolet (UV) spectroscopy, and Fourier transform infrared (FTIR) analysis were used. High decolourization efficiency was achieved under ideal conditions, reaching more than 91 percent color removal. The obtained results from all the previous techniques revealed that the optimal dye removal conditions are as follows: 60 minutes and 1200 mv applied potential. To detect the corrosion influence of the treated dye effluent (at different conditions) on the stainless steel, some of the electrochemical measurements (Potentiodynamic polarization PDP, and electrochemical impedance EIS) and morphological investigation (scanning electron microscope (SEM) and energy dispersive X-ray (EDX)) were also applied. It is showed that the more purity of the dye effluent, the less corrosion rate obtained. Finally the electrocoagulation process achieved good results in the purification of dye wastewater.