Adsorption of Cd (II) and Hg (II) from aqueous phase by adsorbent prepared from Cassia tora fruit shell

Abstract

The Cd (II) and Hg (II) are highly toxic when enters into the body of a living being. Present study describes the adsorption behaviour of these metal ions from aqueous phase using Cassia tora fruit shell substrate. The effect of various parameters like pH, contact time, initial metal ion concentration, doses of adsorbent and temperature on adsorption of metal ions was studied. Freundlich and Langmuir adsorption isotherm best fitted with experimental data. The adsorption capacity for Cd (II) and Hg (II) at pH 6 for optimum contact time of 75 minutes at 100 ppm concentrations was found to be 27.247 and 12.545 mg g-1, respectively. An effective adsorption of about 85-92% of metal ions was observed in single batch. The temperature has inverse effect on extent of adsorption of metal ions and it increases with doses of substrate. The fruit shell substrate was found to be efficient medium for removal of Cd (II) and Hg (II) ions from aqueous solution.