This study investigates optimization of various competitive adsorption parameters for removal of Cd(II), Ni(II) and Pb(II) from aqueous solutions by commercial activated carbon (AC) using the Taguchi method. Adsorption parameters such as initial metal concentration of each metal ion (C0, i), initial pH (pH0), adsorbent dosage (m) and contact time (t) in batch technique were studied to observe their effects on the total adsorption capacity of metals onto activated carbon (qtot). The adsorbent dosage has been found to be the most significant parameter. Interactions between C0, Cd× C0, Ni, C0, Cd×C0, Pb and C0, Ni×C0, Pb have been considered for simultaneous metal ions adsorption. The optimum condition for adsorption of metal ions were obtained with C0, i=100 mg L^(-1), pH0=7, m=2 g L^(-1) and t=80min. Finally, experimental results showed that a multi-staged adsorptive treatment would be necessary to reach the minimal discharge standards of metal ions in the effluent.
Taguchi G, Jugulum R, The Mahalanobis-Taguchi Strategy, Wiley, New York, 2002
Mason RL, Gunst RF, Hess JL, Statistical design and analysis of experiments with applications to engineering and science, Wiley-Interscience, New Jersey, 2003