Evaluation of the Adsorption of Hexavalent Chromium on Kaolinite and Illite
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Abstract
The adsorption of hexavalent chromium on Kaolinite and Illite was studied in order to evaluate their potential for the reduction of hexavalent chromium mobility and their possible application for the treatment of polluted sediment. The influence of various parameters affecting the adsorption of hexavalent chromium, such as the pH of aqueous solution, the ionic strength and the initial metal ion concentration were investigated. The optimal pH range corresponding to the hexavalent chromium adsorption maximum on the Kaolinite and Illite is 2 - 4 and 2 - 2.6, respectively. The results showed that hexavalent chromium sorption on Kaolinite and Illite was strongly influenced by the pH, the ionic strength and the initial metal ion concentration. Langmuir and Freundlich adsorption isotherms are employed to understand the nature of adsorption at room temperature. The characteristic parameters for each isotherm have been determined. This showed that the Freundlich isotherm model well described the equilibrium data. The data suggest that the charge of the clay mineral surface is one of the main factors controlling hexavalent chromium desorption at alkaline pHs.
- D. E. Kimbrough, Y. Cohen, A. M. Winer, L. Creelman and C. Mabuni, “A Critical Assessment of Chromium in the Environment,” Critical Reviews in Environmental Science and Technology, Vol. 29, No. 1, 1999, pp. 1-46. doi:10.1080/10643389991259164
- J. Kota? and Z. Stasicka, “Chromium Occurrence in the Environment and Methods of Its Speciation,” Environmetal Pollution, Vol. 107, No. 3, 2000, pp. 263-283. doi:10.1016/S0269-7491(99)00168-2
- Agency for Toxic Substances Disease Registry (ATSDR), “Toxicological Profile for Chromium,” Atlanta, 2000.
- World Health Organization (WHO), “Guidelines for Drinking-Water Quality,” Incorporating 1st and 2nd Addenda, 3rd Edition, Vol. 1, Recommendations, Geneva, 2008.
- US Environmental Protection Agency (US EPA), “Gui- delines for Water Reuse,” Office of Wastewater Manage- ment Office of Water, Washington DC, 2004, EPA/R- 04/108
- Y. Xi, M. Mallavarapu and R. Naidu, “Preparation, Characterization of Surfactants Modified Clay Minerals and Nitrate Adsorption,” Applied Clay Science, Vol. 48, 2010, pp. 92-96. doi:10.1016/j.clay.2009.11.047
- C. D. Palmer and R. W. Puls, “Natural Attenuation of He- xavalent Chromium in Groundwater and Soils,” US EPA, Ground Water Issue, 1994, EPA/540/5-94/505.
- O. Ajouyed, C. Hurel, M. Ammari, L. B. Allal and N. Marmier, “Sorption of Cr(VI) onto Natural Iron and Aluminum (Oxy)Hydroxides: Effects of pH, Ionic Strength and Initial Concentration,” Journal of Hazardous Materials, Vol. 174, No. 1-3, 2010, pp. 616-622. doi:10.1016/j.jhazmat.2009.09.096
- B. Baeyens and M. H. Bradbury, “A Mechanistic Description of Ni and Zn Sorption on Na-Montmorillonite Part I: Titration and Sorption Measurements,” Journal of Contaminant Hydrology, Vol. 27, No. 3-4, 1997, pp. 199- 222. doi:10.1016/S0169-7722(97)00008-9
- F. J. Huertas, L. Chou and R. Wollast, “Mechanism of Kaolinite Dissolution at Room Temperature and Pressure: Part 1. Surface Speciation,” Geochimica et Cosmochimica Acta, Vol. 62, No. 3, 1998, pp. 417-431. doi:10.1016/S0016-7037(97)00366-9
- G. M. Beene, R. Bryant and D. J. A. Williams, “ElectroChemical Properties of Illites,” Journal of Colloid and Interface Science, Vol. 147, No. 2, 1991, pp. 358-369. doi:10.1016/0021-9797(91)90168-8
- T. H. Herrington, A. Q. Clarke and J. C. Watts, “The Surface Charge of Kaolin,” Colloids and Surfaces, Vol. 68, No. 3, 1992, pp. 161-169. doi:10.1016/0166-6622(92)80200-L