Characterization of bentonitic clays and their use as adsorbent

Bentonite clay minerals belonging to the smectite group have a wide range of chemical and industrial uses. The structure and chemical composition, exchangeable ion type and small crystal size of smectite are responsible for several properties, including a large chemically active surface area, a high cation exchange capacity and inter-lamellar surface having unusual hydration characteristics. A sample collected from Zaghouan (mideastern Tunisia), was studied by some physico-chemical methods. Results of X-ray diffraction, chemical analysis, infrared spectroscopy, thermogravimetric (TGA) and differential thermal analysis (DTA), cation exchange capacities, specific and total surface, confirm the general smectite character of the collected sample.