Process Conditions and Kinetics for the Removal of Copper from Water by Electrocoagulation

The present study provides results from a study of the removal of copper from water through electrochemically generated Al3+ using aluminium alloy as the electrodes. Various operating conditions on the removal efficiency of copper were investigated, such as initial copper ion concentration, initial pH, current density, and temperature. Results showed that the optimum removal efficiency of 98.5% was achieved at a current density of 0.025 A/dm(2), at pH of 7.0. Effects of co-existing anions such as carbonate, phosphate, silicate, and fluoride were studied on the removal efficiency of copper. Results of pilot scale study show that the process was technologically feasible. Adsorption of copper could be described by the Langmuir adsorption isotherm suggesting monolayer coverage of adsorbed molecules. First- and second-order rate equations, Elovich and Intraparticle diffusion models, were applied to study adsorption kinetics. The adsorption process follows the second-order kinetics model with good correlation. Temperature studies showed that adsorption was endothermic and spontaneous in nature.