Kinetics and Thermodynamics of Some Heavy Metals Removal from Industrial Effluents Through Electro-Flotation Process

摘要

The electrokinetic of chromium, copper, silver and gold ions removal from synthetic and wastewater via electro-flotation was investigated. Kinetics and thermodynamic parameters of the electro-flotation process were determined. The effect of initial pH and metal ion concentration, treatment time and temperature showed that the maximum removal was achieved at pH 6. The order of the metal ions removal is Crsup3+/sup Cusup2+/sup Agsup+/sup Ausup+/sup. The removal process follows pseudo first-order kinetics and the adsorption is a heterogeneous system characterized by physical adsorption which is exothermic. Negative values of entropy change ΔS° and Gibbs free energy change ΔG° indicate that this adsorption process is spontaneous and less favorable at high temperatures. The treatment of electroplating wastewater showed that the removal efficiency was ranging between 96 - 99%. The electrical energy consumption was 0.033 Kwh/L.