Research Information System
Separation and Purification Technology, vol.51, no.3, pp.240-246, 2006 (SCI-Expanded)
In this paper, the Cd(II) adsorption abilities of pyrite and synthetic iron sulphide (SIS) were studied. Experiments were carried out as a function of pH, Cd(II) concentration, contact time and temperature. Maximum adsorption yields for pyrite and SIS were determined to be 34.2% and 65.8% under the conditions of initial Cd(II) concentration of 100 mg/l, pH 5.4, contact time of 120 min and adsorbent dosage of 20 g/l, respectively. The adsorption data fitted both the Langmuir and Freundlich adsorption models. Adsorption capacities of SIS and pyrite at 25 °C were found to be 3.05 and 2.08 mg Cd(II)/g, respectively. The first-order and pseudo second-order rate expressions were applied to experimental data and it was determined that the adsorption process followed the first-order kinetic model. In addition, activation energy values and some thermodynamic parameters such as ΔG°, ΔH° and ΔS° for the cadmium adsorption processes were calculated from the isotherm and kinetic data. The adsorption of Cd(II) on to SIS and pyrite was found to be endothermic and spontaneous. © 2006 Elsevier B.V. All rights reserved.