Radiochemical study of Co2+ sorption on chlorite and kaolinite

In this work, the sorption behavior of Co(II) ions on natural chlorite and kaolinite as a function of time, concentration and temperature was studied. Co-60 radiotracer method and the batch technique were used. The kinetic re sults indicated that about one day of contact time was enough to achieve eq uilibrium. The sorption process was described by Freundlich type isotherms. Sorption of Co(II) ions on both clays was found to be endothermic with Del ta H degrees (kJ/mol) and Delta S degrees (kJ/mol.K) being 33 and 0.14 for kaolinite and 17 and 0.102 for chlorite, respectively. The magnitudes of th e corresponding Delta G degrees values suggest that sorption occur mainly v ia an ion exchange mechanism on both clays.