Revista de Engenharia Química e Tecnologia de Processos
Acesso livre

Abstrato

Comparative Study of Bivalent Cationic Metals Adsorption Pb(II), Cd(II), Ni(II) and Cu(II) on Olive Stones Chemically Activated Carbon

Thouraya Bohli, Isabel Villaescusa and Abdelmottaleb Ouederni

In this work the ability of olive stone activated carbon (COSAC) to remove Pb(II), Cd(II), Ni(II) and Cu(II) metal ions from aqueous solutions was evaluated. The effect of initial pH, contact time and initial concentration on metal ions adsorption was investigated. The results indicated that pH 5 is the optimum value for metal removal. Adsorption kinetic rates were found to be fast; total equilibrium was achieved after 4 hours. Kinetic experimental data fitted very well the pseudo-second order equation and the values of adsorption rate constants were calculated. The equilibrium isotherms were evaluated in terms of maximum adsorption capacity and adsorption affinity by the application of Langmuir and Freundlich equations. Results indicate that the Langmuir model fits adsorption isotherm data better than the Freundlich model. The removal efficiency of heavy metal ions by COSAC decreases in the order Pb(II) >Cd(II) > Ni(II) ≥ Cu(II).