Physicochemical characterization of organophilic clay

Organophilic smectite were obtained by intercalation of hexadecyltrimethyl ammonium bromide (HDTMA) in the interlayer space of a purified Tunisian sodic-smectite. The HDTMA amounts were varied from 0.5 to 3 times the cation exchange capacity (CEC) of the purified clay. Adsorption isotherm shows a total adsorption of HDTMA by purified smectite when the quantity of salt is less or equal to 2 CEC. Beyond this value, adsorption becomes limited and tends to saturation. All organoclays were characterized by X-ray diffraction which shows an increase of the basal distance. Infrared spectroscopy and differential thermic and thermogravimetric analysis results confirm the intercalation HDTMA.