Study of the Adsorption Performance of a Cationic Dye onto a Moroccan Clay

The purpose of this study is to examine the adsorption process of a cationic dye, in this case Methylene Blue (MB), on Moroccan natural clay collected from Marrakech region. The influence of physicochemical parameters (contact time, pH, mass of the adsorbent, initial Methylene Blue concentration and temperature) on MB adsorption performance on clay was studied. Experimental results showed a remarkable and rapid elimination within the first twenty minutes of contact of the two phases. The adsorption kinetics of Methylene Blue was evaluated applying pseudo first and second order kinetic models. The kinetic study demonstrates that adsorption obeys the pseudo second order model. The adsorption process was determined by applying the Langmuir and Freundlich isotherms. The maximum adsorption capacity of the raw clay is about 32 mg g-1. The temperature effect on dye adsorption was also examined and thermodynamic parameters were calculated.