Electrochemical Treatment of Electroplating Wastewater Using Carbon and Aluminum Electrodes

Abstract

Heavy metal ions are frequently of high toxicity and require treatment to allowable standards for wastewater discharge. Electrochemical methods are more suitable for heavy metals removal because they can reduce metal concentration to the ppm range and allow recovery of valuable metal. The aim of this work is to treat electroplating wastewater using the electochemical corrosion of the sacrificial soluble alumnium electodes and insoluble carbon electrode using ferric chloride or alum as coagulant. Several working parameters, such as current intensity, electrode material, pH and time were tested. Results revealed that the best removal was achieved at 30 minutes and a potential difference 15 volt for aluminum electrode and10 volts for carbon electrode with ferric chloride. The removal efficiency percentage for synthetic solution of zinc, copper and nickel is 97.2%, 97% and 96% respectively and for factory sample is 80%, 76.6% and 93.4% using aluminum electrode and for carbon electrode using ferric chloride to 97.5%, 97.2% and 97.1%. and for factory sample is 81.6%, 77.3% and 94.4%. The use of carbon electrode with FeCl3 is more suitable than aluminum electrode due to the dissolution of aluminum ions from electrode in the solution.