The adsorption of Cu (II) from aqueous solutions on the surface of activated charcoaI was investigated as a function of shaking time, concentration of adsorbate, and shaking temperatures of 25°C, 30°C, 35°C, °C 40°C, 45°C and 50°C. For this purpose, high purity CuCl2 was used as the heavy metal source and commercial activated charcoal was used as the adsorbent Adsorption equilibrium was attained within 20 minutes. The adsorption was lower at higher temperatures and vice versa, due to the exothermic nature of the process. Accordingly the energy of activation is small, and thus these reaction are favorable at lower as compared to high temperatures. Freundlich and Langmuir adsorption isotherms were applied to the data and it was found that both equation fitted the data well. The rate constants of adsorption were determined by the first order kinetic equation which provided best fit to the data, indicating that the kinetics of the surface adsorption process are directly proportional to the adsorbate concentration. The adsorption isotherm data was also used for computing the thermodynamic parameters like DG¹, DH¹and DS¹. Negative value of these parameters show that the interaction of the adsorbate with the adsorbent is spontaneous.


MANZOOR IQBAL ,SULTAN ALAM ,FAZLULLAH KHAN BANGASH ,