<b>KINETIC STUDIES ON THE SORPTION OF LEAD AND CADMIUM IONS FROM AQUEOUS SOLUTIONS BY <i>CALADIUM BICOLOR</i> (WILD COCOYAM) BIOMASS</b>

Abstract

Kinetic investigations are necessary for determining the rate of reaction and mechanism. The kinetics of the sorption of Pb²⁺ and Cd²⁺ from aqueous solution on to the biomass of C. bicolor was studied by batch equilibrium technique. The removal of the two metal ions was found to be > 60% depending on the initial metal ion concentration during the contact time. The maximum sorption was found to be 75.11 mg/g and 25.30 mg/g for Pb²⁺ and Cd²⁺ at an equilibrium contact time of 150 min. The process of uptake is governed by film-diffusion controlled pseudo-second order reversible rate kinetics. The sorption capacity at any contact time has been evaluated and a Langmuir-type model equation has been developed to predict the optimized minimum operating time to determine a specific amount of metal ion sorption.



KEY WORDS: Sorption kinetics, Contact time optimization, Water treatment, Heavy metals removal


Bull. Chem. Soc. Ethiop. 2005, 19(1), 89-102.