Adsorption isotherm and kinetics studies of cadmium (II) ions removal using various activated carbons derived from agriculture bark wastes: A comparative study

M. Syed Meera and T. K. Ganesa

Abstract

This paper reports the feasibility of using various indigenously prepared activated carbons (IPACs) derived from agricultural residues viz., Eucalyptus Bark (Eucalyptus Globules), Neem Bark (Azadirachta Andica), Tamarind Bark (Tamarindus indica), Mango bark (Mangifera indica), Emblica Bark (Phyllanthus emblica) for the removal of Cd(II) from aqueous solution under different experimental conditions. Effect of various process parameters, viz., initial metal ion concentration, agitation time, initial solution pH and adsorbent dose has been studied for the removal of cadmium. The applicability of Langmuir and Freundlich isotherm suggests the formation of monolayer of Cd(II) ions onto the outer surface of the adsorbents. Moreover, the adsorption data are modeled with various first order kinetic equations like Natarajan-Khalaf, Lagergren and Bhattacharya-Venkobachar equations. Order of Cd(II) removal by various adsorbents is CAC>>EGBC >NBC>TBC>MBC>EOBC.