Improvement of Fe(Ii)-Adsorption Capacity of Feooh-Coated Brick in Solutions, and Kinetics Aspects

HTML  Download Download as PDF (Size: 379KB)  PP. 464-473  
DOI: 10.4236/jwarp.2012.47054    3,583 Downloads   6,406 Views  Citations

ABSTRACT

The adsorbent, iron oxy-hydroxide coated brick, was used in the present work for removal of iron(II) from aqueous solutions. The adsorption performances of this composite were significantly improved when brick pellets (as a support material) were pre-treated in a 6 M HCl solution at 90°C for 6 hours, when compared to untreated ones and those pre-washed in a 1M HCl solution at RT for 1 day. This phenomenon was attributed to larger surface areas measured for modified brick by BET, thus enabling a better FeOOH deposition. The ability of this new composite to better adsorb Fe2+ ions from synthetic solutions was evidenced from fixed-bed column experiments: data were compared to those obtained from raw brick and iron oxides - coated sand columns. The adsorption mechanism followed better pseudosecond-order reaction kinetics, suggesting a chemisorption process, and the rate constant increased with a temperature increase, revealing the endothermic nature of Fe(II) adsorption. Furthermore, the equilibrium data fitted the Langmuir isotherm model with a maximum monolayer sorption capacity Qmax = 0.669 mg/g and a Langmuir constant KL = 0.659 L/mg at room temperature. The activation energy (Ea) of Fe(II) adsorption and the changes in entropy (ΔS), enthalpy (ΔH) and free energy (ΔG) of activation were determined, with values suggesting the involvement of an activated chemical adsorption and an associative mechanism.

Share and Cite:

S. Charles Dehou, J. Mabingui, L. Lesven, M. Wartel and A. Boughriet, "Improvement of Fe(Ii)-Adsorption Capacity of Feooh-Coated Brick in Solutions, and Kinetics Aspects," Journal of Water Resource and Protection, Vol. 4 No. 7, 2012, pp. 464-473. doi: 10.4236/jwarp.2012.47054.

Copyright © 2024 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.