Removal of cadmium (II) ions from aqueous solution by Tamrix gallica leaves

Removal of cadmium from aqueous solutions by Tamrix gallica leaves has been investigated. The effect of several factors on the removal has been studied, including metal ions concentration, Tamrix leaves concentration, pH, presence of competing ions, agitation, crushing, and drying. Removal of cadmium by Tamrix leaves was found to be dependant on pH and the maximum removal of cadmium by Tamrix leaves was found at pH 5. The cadmium removal by Tamrix leaves has been found to depend on both the concentration of leaves and the concentration of cadmium in solution. The presence of foreign ions along with cadmium ions in water reduce the removal of cadmium in the order Cu > Pb > Ni > Na > K. Applicability of the Freundlich adsorption isotherm has been examined and the parameters of this isotherm have been calculated. The order of reaction between cadmium ions and Tamrix gallica leaves with respect to cadmium has been found to be first order and a mechanism based on adsorption of cadmium on leaves has been suggested. Key words: cadmium removal, water, Tamrix leaves, adsorption isotherm.