Understanding the Adsorption Efficiency of Chitosan Coated Carbon on Heavy Metal Removal

In the present study, the performance of chitosan coated carbon was evaluated for the removal of chromium (VI) and cadmium (II) from its aqueous solution. The chitosan coated carbon was prepared and characterized by using the various analytical tools such as FTIR, TGA, DSC and XRD. Batch adsorption experiments were performed in order to examine the effects of initial concentration, pH, and adsorbent dose and contact time for the removal process. The metal ion removal was pH-dependent. The optimum pH was found to be 5.0 for Cr (VI) and 5.5 for Cd (II). Experimental data were analyzed by Langmuir and Freundlich adsorption isotherms. The characteristic parameters for each isotherm and related correlation coefficients have been determined. The isotherm study revealed that the adsorption equilibrium is well-fitted to the Freundlich isotherm for both the metals. The kinetics study revealed that adsorption of Cr (VI) and Cd (II) onto chitosan coated carbon follows pseudo-second-order kinetics. The results showed that chitosan coated carbon were a favorable adsorbent for both the metals.