Removal of Pb(II) and Cr(VI) by laterite soil from synthetic waste water: single and bi-component adsorption approach

Abstract

Abstract: Adsorption of Pb(II) and Cr(VI) on laterite soil adsorbent from aqueous solution has been studied as a function of pH, contact time, adsorbent dose, and initial concentration through single and bi-component approach in batch reactor. The optimum conditions for both metals are found as pH 6, contact time 240 min, adsorbent dose 10 g/L, and initial concentration 20 mg/L for single component adsorption. Kinetics and equilibrium adsorption data of single component adsorption fit well to the pseudo-second-order kinetic model and Freundlich isotherm model, respectively. Under the experimental conditions, adsorption of Pb(II) is found to be more than that of Cr(VI) for both single component and bi-component systems. The combined adsorptions of Pb(II) and Cr(VI) in single and bi-component systems do not differ much. The extended Freundlich model is found to best represent the equilibrium adsorption phenomena in bi-component system. © 2015 Balaban Desalination Publications. All rights reserved.