Investigations for Modification of Polyacrylamide-Bentonite by Phytic Acid and its Usability in Fe3+, Zn2+ and UO2 2+ Adsorption
Tóm tắt
Composite of polyacrylamide-bentonite (PAA-B) was prepared by direct polymerisation of PAA in a suspension of bentonite (B). Adsorption and thermodynamic features of phytic acid (Phy) adsorption onto B, PAA and PAA-B, and those of Fe3+, Zn2+, UO2
2+ adsorption onto PAA-B and its modification by Phy (PAA-B-Phy) have been investigated. The reusability, storagability, ion selectivity and recoverability of sorbed ions with 1 M HCl have also been considered. The chemical and physical structure of adsorbents has been characterised by means of FT-IR and XRD. All adsorption isotherms for Phy and the ions were L-type of the Giles classification except, the one which is S type for adsorption of Phy onto PAA. The maximum adsorption capacities for the ions adsorbed were in order of UO2
2+ > Fe3+ > Zn2+ for PAA-B and Zn2+ > Fe3+ > UO2
2+ for PAA-B-Phy. Langmuir equilibrium constants for the adsorption of ions onto PAA-B-Phy were significantly higher than those found for PAA-B; the magnitude of increase for UO2
2+ was about 100. The thermodynamic parameters indicated that adsorption reactions are spontaneous in terms of adsorption free enthalpy. The chemical structure of PAA-B-Phy was not changed at the end of the studies of reusability and storagability. The composite was selective for UO2
2+ of the ions of interest. The composite of PAA-B and its modification by Phy have been used for the first time in this investigation. It is proposed that the composites can be practically used in the investigations and applications of adsorption.
Tài liệu tham khảo
Altın, O., H. Ö. Özbelge, and T. Doğu, “Use of General Purpose Adsorption Isotherms for Heavy Metal-Clay Mineral Interactions,” J. Colloid Interface Sci., 198, 130–140 (1998).
Atun, G., G. Hisarlı, and M. Tunçay, “Adsorption of Safranine-O on Hydrophilic and Hydrophobic Glass Surfaces,” Coll. Surf., 143, 27–33 (1998).
Bajpai, A.K. and R. Sachdeva, “Adsorption of Casein onto Alkali Treated Bentonite,” J. Appl. Polym. Sci., 78, 1656–1663 (2000).
Borovec, Z., “The Adsorption of Uranyl Species by Fine Clay,” Chemical Geology, 32,45–48 (1981).
Brooks, S.P.J. and B.J. Lampi, “Problems Associated with Measuring Phytate in Infant Cereals,” J. Agric. Food Chem., 49, 564–569 (2001).
Carrado, K.A. and L. Xu, “ın Situ Synthesis of Polymer-Clay Nanocomposites from Silcate Gels,” Chem. Matter., 10, 1440–1445 (1998).
Celis, R., M.C. Hermosin, and J. Cornejo, “Heavy Metal Adsorption by Functionalized Clays,” Environ Sci. Technol., 34, 4593–4599 (2000).
Ceyhan, Ö., H. Güler, and R. Güler, “Adsorption Mechanisms of Phenol and Methylphenols on Organoclays,” Ads. Sci. Technol., 17, 469–477 (1999).
Chisholm-Brause, C., S.D. Conradson, C.T. Buscher, P.G. Eller, and D.E. Morris, “Speciation of Uranyl Sorbed at Multiple Binding Sites on Montmorillonite,” Geochim. Cosmochim. Acta., 58, 3625–3631 (1994).
Dai, S., Y.S. Shin, C.E. Barnes, and L.M. Toth, “Enhancement of Uranyl Adsorption Capacity and Selectivity on Silica Sol-Gel Glasses Via Molecular Imprinting,” Chem. Mater., 9, 2521–2525 (1997).
De Boland, A.R., G.B. Garner, and B.L. O'Dell, “Identification and Properties of “Phytate” in Cereal Grains and Oilseed Products,” J. Agric. Food. Chem., 23, 1186–1189 (1975).
Domb, A.J., E.G. Cravalho, and R. Langer, “The Synthesis of Poly(hydroxamic Acid) from Poly(acrylamide),” J. Polym. Sci. Poly. Chem., 26, 2623–2630 (1988).
Eligwe, C.A., N.B. Okolue, C.O. Nwambu, and C.I.A. Nwoko, “Adsorption Thermodynamics and Kinetics of Mercury(II), Cadmium( II) and Lead(II) on Lignite,” Chem. Eng. Technol., 22,45–49 (1999).
Frossard, E., M. Bucher, F. Machler, A. Mozafar, and R. Hurrell, “Potential for Increasing the Content and Bioavailability of Fe, Zn and Ca in Plants for Human Nutrition,” J. Sci. Food Agric., 80, 861–879 (2000).
Giles, C.H., T.H. MacEwan, S.N. Nakhwa, and D. Smith, “Studies in Adsorption. Part XI. A System of Classification of Solution Adsorption Isotherms, and Its Use in Diagnosis of Adsorption Mechanisms and in Measurement of Spesific Surface Areas of Solids,” J. Chem. Soc., 3973–3993 (1960).
Greenwood, N.N. and A. Earnshaw, Chemistry of The Elements, Butterworth-Heinemann Ltd., Cambridge, 1995.
Grim, R.E., Clay Minerology, Mc Graw Hill, New York, 1968.
Güven, O. and P. Akkas, “Enhancement of Uranyl Ion Uptake by Prestructuring of Acyrlamide—Maleic Acid Hydrogels,” J. Appl. Polym. Sci., 78, 284–289 (2000).
Haderlein, S.B., K.W. Weissmahr, and R.P. Schwarzenbach, “Specific Adsorption of Nitroaromatic Explosives and Pesticides to Clay Minerals,” Environ Sci. Technol., 30, 612–622 (1996).
Jin, W. and S. Zhu, “Study of Adsorption Equilibrium and Dynamics of Benzene, Toluene, and Xylene on Zeolite NaY,” Chem. Eng. Technol., 23, 151–156 (2000).
Lagadic, I.L., M.K. Mitchell, and B.D. Payne, “Highly Effective Adsorption of Heavy Metal Ion by a Thiol-Functionalized Magnesium Phyllosilicate Clay,” Environ Sci. Technol., 35, 984–990 (2001).
Lagaly, G., “Introduction: From Clay Mineral-Polymer Interactions to Clay Mineral-Polymer Nanocomposites,” Appl. Clay. Sci., 15, 1–9 (1999).
Loewus, F.A. and M.W. Loewus, “Myo-Inositol: Its Biosynthesis and Metabolizm,” Ann. Rev. Plant Physiol., 34, 137–161 (1983).
Luckham, P.F. and S. Rossi, “The Colloidal and Rheological Properties of Bentonite Suspensions,” Adv. Colloid Interface Sci., 82, 43–92 (1999).
Lurie, Ju., Handbook of Analytical Chemistry, Mir Publishers, Moscow, 1975.
Miller, J.C. and J.N. Miller, Statistics for Analytical Chemistry, John Wiley & Sons, New York, 1989.
O'Neill, I.K., M. Sargent, and M.L. Trimble, “Determination of Phytate in Foods by Phosphorus-31 Fourier Transform Nuclear Magnetic Resonance Spectrometry,” Anal. Chem., 52, 1288–1291 (1980).
Panayotova, M., “Kinetics of Heavy Metal Ions Removal from Wastewater by Natural Zeolite in the Presence of Calcium and Magnesium,” J. Environ. Protec. Eco., 3, 350–355 (2000).
Pefferkorn, E., “Polyacrylamide at Solid/Liquid Interfaces,” J. Coll. and Inter. Sci., 216, 197–220 (1999).
Rauf, N. and S.S. Tahir, “Thermodynamics of Fe(II) and Mn(II) Adsorption onto Bentonite from Aqueous Solutions,” J. Chem. Therm., 32, 651–658 (2000).
Shi, H., T. Lan, and J. Pinnavaia, “Interfacial Effects on the Reinforcement Properties of Polymer-Organoclay Nanocomposites,” Chem. Mater., 8, 1584–1587 (1996).
Singh, V.K. and P.N. Tiwari, “Removal and Recovery of Chromium(VI) from Industrial Waste Water,” J. Chem. Tech. Biotechnol., 69, 376–382 (1997).
Starodoubtsev, S.G., N.A. Churochkina, and A.R. Khokhlov, “Hydrogel Composites of Neutral and Slightly Charged Poy-( acrylamide) Gels with Incorporated Bentonite. Interaction with Salt and Ionic Surfactants,” Langmuir., 16, 1529–1534 (2000).
Theng, B.K.G., The Chemistry of Clay-Organic Reactions, John Wiley & Sons, New York, 1974.
Tsao, G.T., Y. Zheng, J. Lu, and C.S. Gong, “Adsorption of Heavy Metal Ions by Immobilized Phytic Acid,” Appl. Bichem. Biotechnol., 63–65, 731–741 (1997).
Van der Maas, J.H., Basic Infrared Spectroscopy, Heyden & Son Ltd., London, 1972.
Vohra, P., G.A. Gray, and F.H. Kratzer, “Phytic Acid-Metal Complexes,” Proc. Soc. Exp. Biol. Med., 120, 447–449 (1965).