Silica gels used were obtained by alkaline attack of Tunisian sand, coming from Feriana region. A kinetic of methylene blue adsorption in liquid phase onto silica gels has been studied. The results show the effects of silica gel pH, initial concentration of methylene blue and temperature on adsorption capacity. Adsorption isotherms have been determined and fitted according to the Langmuir and Guggenheim N Anderson NDe Boer (G.A.B.) equations. A high adsorptive capacity was observed. Thermodynamic parameters such as ∆H and ∆S were determined.
M. Besbes, N. Fakhfakh, M. Benzina
silica gel, adsorption, isotherms, kinetics, modelling