Cadmium Adsorption on HDTMA Modified Montmorillionite

Mohd. Elmuntasir I. Ahmed

Abstract


In this paper the possibility of cadmium removal from aqueous solutions by adsorption onto modified montmorillonite clay is investigated. Batch adsorption experiments performed revealed an enhanced removal of cadmium using HDTMA modified montmorillonite to 100% of its exchange capacity. Modified montmorillonite adsorption capacity increases at higher pHs suggesting adsorption occurs as a result of surface precipitation and HDTMA complex formation due to the fact that the original negatively charged montmorillonite is now covered by a cationic layer of HDTMA. Adsorption isotherms generated followed a Langmuir isotherm equation possibly indicating a monolayer coverage. Adsorption capacities of up to 49 mg/g and removals greater than 90% were achieved. Anionic selectivity of the HDTMA modified monmorillonite is particularly advantageous in water treatment applications where high concentrations of less adsorbable species are present, and the lack of organoclay affinity for these species may allow the available capacity to be utilized selectively by the targeted species.

 


Keywords


Environmental quality, Adsorption, Montmorillonite, Cadmium removal

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References


Ahmed, M.I., 1996, Modified Clays for the Removal of Cadmium from Aqueous Media. MSCE thesis, Bradley Universiy, Peoria, IL, USA.

Allison Geoscience Consultants, Inc. and HydroGeoLogic, Inc., 2003, MINTEQA2 for WindowsEquilibrium Speciation Model version 1.50, Flowery Branch, GA, USA.

Barrer, R.M. and MacLeod, D.M., 1955, "Activation of Montmorillionite by Ion Exchange and Sorption Complexes of Tetra-Alkylammonium Montmorillionites," Transactions of Faraday Society, Vol. 51, pp. 1290-1300.

Barrer, R.M., 1978, "Ziolites and Clay Minerals as Sorbents and Molecular Sieves," Academic Press, London.

Barrer, R.M., 1989, "Clay Minerals as Selective and Shape Selective Sorbents," Pure and Applied Chemistry, Vol. 61, pp. 1903-1912.

Brindley, G.W., Wiewiora, K. and Wiewiora, A., 1969, "Intercrystalline Swelling of Monmorillonite in some Water Organic Mixtures," Clay-organic Studies, Part XVII." American Mineralogist, Vol. 43, pp. 106-115.

Earley, J.W., Osthaus, B. and Milne, I.H., 1953, "Purification and Properties of Montmorillonite," American Mineralogist, Vol. 7-8, pp. 102-108.

Foster, M.D., (1953). " Geochernical studies of clay minerals (II): Relation between ionic substitution and swelling in montmorillonite." American Mineralogist, 11-12, 143-154.

Grim, R.E., (1968), Clay Mineralogy, (ed. 2) McGraw Hill Book Company, New York.

Haggerty, G.M., Bowman, R.S., (1994). "Sorption of chromate and other inorganic anions by organo-ziolite." Environmental Science and Technology, 28, 3, 452- 458.

Jamrah, A.I. and Dentel, S.K. (1993). "Application of Organoclays to Water Treatment: Selective Removal of Trichlorophenol." Proc. 1993 AWWA Ann. Conf., San Antonio.

Katsuhiko, I. and Junta, Y., (2006). " Sorption and desorption properties of Cadmium and Copper on soil clays in relation to charge characteristics." Soil Science and Plant Nutrition, 52, 5-18.

Najm, I.N., Snoeeyink, V.L., Lykins B.W., and Adams, J.Q, (1991). "Using powdered activated carbon: a critical review." Journal American Water Works Association, 83,1,65.

Pourbaix, M., (1974). Atlas of Electrochemical Equilibria in Aqueous Solutions, National Association of Corrosion Engineers, Houston, TX, USA.

Snoeyink, V.L, Jenkins, D., (1980). Water Chemistry, 1st ed., John Wiley & Sons Inc., NJ.

Weber, W.J. (1972). Adsorption, in Physicochemical Processes for Water Quality Control. 1st ed., NY:John Wiley & Sons.




DOI: http://dx.doi.org/10.24200/tjer.vol6iss1pp8-14

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