Studies on the removal of some toxic metal ions. Part II (removal of lead and cadmium by montmorillonite and kaolinite)

Abstract

Abstract Clay samples (montmorillonite and kaolinite) have been characterised and used for the removal of lead and cadmium metals. The adsorption of Pb2+ and Cd2+ is greater on montmorillonite, and the sorption capacity increases with increasing pH. Adsorption on montmorillonite follows the Langmuir model. The uptake is found to decrease in the presence of cationic surfactants while the anionic surfactants enhance the removal of the two metal ions. Kinetic runs were made to have an idea of the mechanistic aspects and obtaining the thermodynamic parameters of the process.