Removal of copper(II) ions from aqueous solution by adsorption on sweet potato peels charcoal.

Abstract

In this study, sweet potato peels charcoal powder was used as an adsorbent for removal of Cu 2+ ions from aqueous solutions. The effect of pH, equilibrium time and initial concentration of Cu 2+ ions on adsorbed amount of Cu 2+ ions were investigated. The Study showed that; The amount of Cu 2+ ions adsorbed increased with increasing bulk solution pH, the amount of Copper adsorbed increased as pH increased from 2.0 to 6.0. This is due to the surface complexation reactions, which are mostly influenced by the electrostatic force of attraction between Copper(II) ions and the surface of the adsorbent. Adsorption of Copper ions increased with increase in initial concentration of adsorbate. This can be attributed to large amount of sweet potato peel charcoal powder used which provided very many adsorption sites sufficient enough for removal of Copper (II) ions from water even at their higher concentration. Adsorption of Copper increased with increase in time. This probably due to larger surface area of finely ground charcoal being available at all times for the adsorption of Copper (II) ions. The experiments showed that the highest removal of Cu 2+ ions was at solution pH 6.0, contact time 8 hours and initial concentration of 0.1mol/dm 3. The experimental data were fitted by the Langmuir adsorption isotherm, suggesting that the adsorption process is presumable a chemisorption.