Removal of cadmium, zinc, manganese and chromium cations from aqueous solution by a clay mineral.

Vermiculite, a 2:1 clay mineral, was applied as adsorbent for removal of cadmium, zinc, manganese, and chromium from aqueous solutions. Parameters such as time of reaction, effect of pH and cation concentration were investigated. All isotherms were L type of the Gilles classification, except zinc (type S). The adsorbent showed good sorption potential for these cations. The experimental data was analyzed by Langmuir isotherm model showing reasonable adjustment. The quantity of adsorbed cations was 0.50, 0.52, 0.60, and 0.48 mmol g(-1) of Cd(2+), Mn(2+), Zn(2+), and Cr(3+), respectively.