A Comparative Study of Clay Minerals for Pollution Control

The structure of montmorillonite provides two exchange sites; one at the surface and the other between the silicate layers. This is confirmed by the dibasic nature of H-montmorillonite. As a consequence, montmorillonite is capable of removing larger amounts of cationic pollutants compared with kaolinite. Anion uptake is relatively feeble and similar for the two clays. A review of recent experiments suggests that clayey soils could act as barriers against dispersion of toxic metals, detergents and dyes.