The Removal of Cadmium (II), Copper (II) and Lead (II) From Aqueous Solutions by Olive Tree Pruning Waste

Abstract

The adsorption ability of ground, sieved and washed olive tree pruning waste (OPW) obtained as twigs from various olive cultivated region of Turkey was investigated for the removal of Cu 2+, Cd 2+ and Pb 2+ ions from aqueous systems. Adsorption of the investigated heavy metal ions by OPW strongly depends on pH, contact time, initial concentration of the heavy metal ions and adsorbent dosage. The highest value of Langmuir maximum uptake, (q <inf>mac</inf>), was found for copper (47.0×10 -5 mol g -1) followed by cadmium (32.6×10 -5 mol g -1) and lead (22.3×10 -5 mol g -1). Similar Freundlich empirical constants, K <inf>F</inf>, were obtained for Cu 2+, Cd 2+ and Pb 2+ ions 0.141, 0.0042 and 0.0045 respectively. The experimental data fitted the Langmuir isotherm model (r 2=0.827-0.967). The approximate value of the pH <inf>pzc</inf> of the OPW was deduced by plotting pH <inf>in</inf> vs pH <inf>eq</inf> values measured during the adsorption experiments. The results show that OPW, which has a very low economical value, may be used in removal of Cd 2+, Pb 2+ and Cu 2+ ions from aqueous systems for environmental cleaning purposes. © by PSP.