THE REMOVAL OF CADMIUM (II), COPPER (II) AND LEAD (II) FROM AQUEOUS SOLUTIONS BY OLIVE TREE PRUNING WASTE

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 Cu2+, Cd2+ and Pb2+ 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(mac)), was found for copper (47.0x10(-5) mol g(-1)) followed by cadmium (32.6x10(5) mol g(-1)) and lead (22.3x10(5) mol g(-1)). Similar Freundlich empirical constants, K-F, were obtained for Cu2+, Cd2+ and Pb2+ 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(pzc) of the OPW was deduced by plotting pH(in) vs pH(eq) values measured during the adsorption experiments. The results show that OPW, which has a very low economical value, may be used in removal of Cd2+, Pb2+ and Cu2+ ions from aqueous systems for environmental cleaning purposes.