Preparation of cetyltrimethylammonium intercalated Indonesian montmorillonite for adsorption of toluene

Organo-clays of cetyltrimethylammonium(CTMA)-intercalated montmorillonite from a naturally occurring Indonesian montmorillonite were prepared. Previous research showed that the insertion of surfactants into interlayer spaces in montmorillonite improved the adsorption of hydrophobic chemicals. The current research focused on the effects of preparation variables, the concentration of CTMA surfactant, the cation exchange capacity (CEC) of the montmorillonite clay and their ratio (CTMA/CEC) on the physicochemical characteristics of the organo-clays and adsorption of toluene. X-ray diffraction (XRD), surface area analysis, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) were used to compare the physicochemical characteristics of the modified and unmodified montmorillonite clays. The adsorption of toluene was studied in kinetics and isotherm. It was found that the CTMA/CEC ratio strongly affected the physicochemical properties and adsorption capacities of the montmorillonite surfaces. Adsorption kinetics was evaluated by pseudo-first order, pseudo-second order and Elovich models. Adsorption isotherm was assessed with the Langmuir, Freundlich and Temkin isotherms. The data were best fit by the pseudo-second order model and the Langmuir model.