Adsorption of Methylene Blue by Hydroxyl-Aluminum Pillared Montmorillonite

A purified raw montmorillonite and hydroxy-aluminum pillared montmorillonite have been prepared from a natural bentonite from Maghnia, Algeria. These materials have been analyzed by X-ray fluorescence spectroscopy, X-ray diffraction, Infrared spectroscopy and nitrogen adsorption-desorption measurement. The pillared montmorillonite provided a certain increase of interlayer basal spacing and BET surface area and consequently the improvement of its capacities adsorption and decolorization of Methylene Blue. The adsorption properties of these materials were studied as a function of contact time, solution pH, initial Methylene Blue concentration and temperature. The adsorption kinetics and isotherms were well fitted by pseudo-second order and Freundlich models, respectively. In addition to that, thermodynamic studies showed an exothermic and a spontaneous process.