EFFICIENCY OF SOME LOW-COST NATURAL PRODUCTS FOR REMOVING COPPER AND LEAD FROM SYNTHETIC POLLUTED WATER

Naglaa I. I. M. Shalaby and Amr M. M. A. Al Nagaawy

Limnology Dept., Central Lab. For Aquaculture Research, Abbassa, ARC.

Received 16/ 2/ 2010 Accepted 24/ 3/ 2010

Abstract

Most available technologies applied in the removal of metal contaminants in aqueous systems use the well established processes of adsorption. Adsorbents currently in use are either too expensive or not readily available for wastewater treatment. There is a need to develop new adsorbents which are readily available at low cost to remove metal contaminants in aqueous system. Thus, the present study aims to investigate the efficiency of maize leaves, banana peels and hens egg shells as inexpensive, widely abundant natural adsorbents to remove heavy metals from synthetic polluted water. Three different concentrations:1, 2 and 3 g/l of each of the investigated materials were tested for their removal efficiency for 5 mg/l Cu and Pb. 2 g/l gave the highest removal efficiency for both Maize leaves and egg shells, while 1 g/l was the best concentration when banana peels were used either for copper or lead. The effect of some experimental parameters such as, solution pH (5, 7 and 9) as well as Contact period (20, 40, 60, 80 and 100 minutes) also has been investigated for their effect on the removal efficiency. Results indicated that the highest removal efficiency percentages were obtained at pH 5 for maize leaves and egg shells and pH 9 for banana peels. Concerning contact period, removal efficiency increase with the increasing in contacting period except for maize leaves where, there were no significant differences between 80 and 100 minutes in case of copper removal, and among different contacting periods in case of lead removal. Application of Langmuir, Freundlich and Temkin isotherm models indicated that using maize leaves for removing lead (R2 = 0.999) and egg shells for removing copper (R2 = 0.93) were highly fitted to Langmuir model. It’s observed that using banana peels for removing lead (R2 = 0.96), maize leaves for removing lead (R2 = 0.886) and egg shells for removing copper (R2 = 0.81), were the most fitted to Freundlich model, while using banana peels for removing lead (R2 = 0.996) and egg shells for removing copper (R2 = 0.696) were the most fitted to Temkin model. Isothermal studies proved that the investigated materials highly potential for removing both copper and lead from polluted water.

Key words: Maize leaves, Banana peels, Hen egg shells, low-cost natural substances.