The application of clays, especially bentonite, has attracted more and more attention because of their low-cost, easy availability, high cation exchange capacity and surface area. Because of their low cost, abundance in most continents of the world, high adsorption properties and potential for ion exchange, clay materials are strong candidates as adsorbents. Bentonite is mainly composed of montmorillonite, which has interlayer cations to compensate the negative net charge on the surface. This negative charge is due to isomorphic substitutions on the montmorillonite structure. These inorganic cations can be replaced with cationic surfactants or polycationic species, and the resulting materials are regarded as organobentonite or pillared bentonite, respectively