Co(II) removal by magnetic alginate beads containing Cyanex 272®

In this study, a series of batch experiments is conducted to investigate the ability of magnetic alginate beads containing Cyanex 272 (R) to remove Co(II) ions from aqueous solutions. Equilibrium sorption experiments show a Co(II) uptake capacity of 0.4 mmol g(-1). The data are successfully modelled with a Langmuir equation. A series of kinetics experiments is then carried out and a pseudo-second order equation is used to fit the experimental data. The effect of pH on the sorption of Co(II) ions is also investigated. Desorption experiments by elution of the loaded beads with nitric acid at pH I show that the magnetic alginate beads could be reused without significant losses of their initial properties even after 3 adsorption-desorption cycles. (C) 2008 Elsevier B.V. All rights reserved.