Adsorption of Toluene in Batch System in Natural Clay and Organoclay

This study aimed to evaluate the adsorption of toluene in two forms of sodium smectite national clays called Fluidgel and produced in northeastern Brazil: commercial and chemically modified with quaternary ammonium salt (hexadecyltrimethylammonium bromide) by the process of organophilization. The commercial Fluidgel and organoclay were characterized by a physical-chemical study evaluating their adsorptive properties and quality from the process of organophilization on the morphology and chemical composition, in relation to their affinity for volatile organic compounds in processes such as BTX adsorption. Toluene adsorption onto clays, commercial and organoclay, with particle diameter of 0.55 mm was carried out in batch system at room temperature with constant stirring. The adsorption study was conducted at initial toluene concentration of 100 ppm, 10 g of clay per liter of effluent and at initial pH of about 6. For kinetic data fitting, pseudo-first-order, pseudo-second-order and intraparticle diffusion models were applied. The results obtained with the characterization analyses showed the efficiency of organophilization process. The adsorption kinetics process showed that the kinetic model of pseudo- second-order was the best fit to experimental data. The adsorption study presented a percentage removal of toluene from about 96 % to equilibrium time of 180 min.