Thermodynamics of Fluoride Adsorption onto Magnesia-amended Activated Carbon

Removal of fluoride from drinking water using magnesia-amended activated carbon (MgO-AC) was investigated. The MgO-AC was characterized scanning electron microscope (SEM). Attempts were made to fit the isothermal data using Langmuir and Freundlich equations. The experimental results have demonstrated that the equilibrium data are fitted well by a Langmuir isotherm model and the maximum sorption capacity of fluoride evaluated is 7.22 mg/g. Thermodynamic parameters of Delta G(0), Delta H-0 and Delta S-0 show that the adsorption is a spontaneous and endothermic process.