Iodide Retention by Modified Kaolinite in the Context of Safe Disposal of High Level Nuclear Waste
Publication: Journal of Hazardous, Toxic, and Radioactive Waste
Volume 16, Issue 3
Abstract
Bentonite clay is identified as potential buffer in deep geological repositories (DGR) that store high level radioactive wastes (HLW) as the expansive clay satisfies the expected mechanical and physicochemical functions of the buffer material. In the deep geological disposal of HLW, iodine-129 is one of the significant nuclides, attributable to its long half-life (). However, the negative charge on the basal surface of bentonite particles precludes retention of iodide anions. To render the bentonite effective in retaining hazardous iodide species in DGR, improvement of the anion retention capacity of bentonite becomes imperative. The iodide retention capacity of bentonite is improved by admixing 10 and 20% Ag-kaolinite (Ag-K) with bentonite (B) on a dry mass basis. The present study produced Ag-kaolinite by heating silver nitrate-kaolinite mixes at 400°C. Marginal release of iodide retained by Ag-kaolinite occurred under extreme acidic () and alkaline () conditions. The swell pressure and iodide retention results of the B-Ag-K specimens bring out that mixing Ag-K with bentonite does not chemically modify the expansive clay; the mixing is physical in nature and Ag-K presence only contributes to iodide retention of the admixture.
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References
Balsley, S. D., Brady, P. V., Krumhansl, J. L., and Anderson, H. L. (1998). “Anion scavengers for low-level radioactive waste repository backfills.” J. Soil Contam.JSOCEZ, 7(2), 125–141.
Breen, C. (1999). “The characterisation and use of polycation-exchanged bentonites.” Appl. Clay Sci.ACLSER, 15(1–2), 187–219.
Bureau of Indian Standards (BIS). (1980a). “Indian standard methods of tests for soils—Part 3.” IS: 2720, Determination of specific gravity of fine grained soils, New Delhi, India.
Bureau of Indian Standards (BIS). (1980 b). “Indian standard methods of tests for soils—Part 7.” IS: 2720, Determination of water content-dry density relation using light compaction, New Delhi, India.
Bureau of Indian Standards (BIS). (1985a). “Indian standard methods of tests for soils—Part 4.” IS: 2720, Determination of grain size analysis, New Delhi, India.
Bureau of Indian Standards (BIS). (1985b). “Indian standard methods of tests for soils—Part 5.” IS: 2720, Determination of liquid and plastic limits, New Delhi, India.
Cotton, F. A., Wilkinson, G., and Gaus, P. L. (1995). Basic inorganic chemistry, 3rd ed., Wiley, New York.
Daniels, E. A., and Rao, S. M. (1983). “Silver sorption by metakaolinite from molten silver nitrate.” Z. Phys. Chem.ZPCFAX, 137(2), 247–254.
Dultz, S., and Bors, J. (2000). “Organophilic bentonites as adsorbents for radionuclides. II. Chemical and mineralogical properties of HDPy—Montmorillonite.” Appl. Clay Sci.ACLSER, 16(1–2), 15–29.
Hesse, P. R. (1971). A textbook of soil chemical analysis, John Murray, London.
Hossner, L. R. (2002). “Dissolution for total elemental analysis.” Methods of soil analysis part-3 chemical methods, Bigham, J. M., ed., Soil Science Society of America, Madison, WI, 49–64.
Inyang, H. I., Bae, S., Mbamalu, G., and Park, S. W. (2007). “Aqueous polymer effects on volumetric swelling of Na-Montmorillonite.” J. Mater. Civ. Eng.JMCEE7, 84–90.
Kallai, L. H. (1978). “Reactions of salts with kaolinite at elevated temperatures. I.” Clay MineralsCLMIAF, 13(2), 221–235.
Kaufhold, S., Pohlmann-lortz, M., Dohrmann, R., and Nuesch, R. (2007). “About possible upgrade of bentonite with respect to iodide retention capacity.” Appl. Clay Sci.ACLSER, 35(2), 39–46.
Mitchell, J. K. (1993). Fundamentals of soil behaviour, Wiley, New York.
Pansu, M., and Gautheyrou, J. (2006). Handbook of soil analysis: Mineralogical, organic and inorganic methods, Springer, New York.
Pennell, K. D. (2002). “Specific surface area.” Methods of soil analysis part 4: Physical methods, Dane, J. H., and Topp, G. C., eds., Soil Science Society of America Book Series No. 5, Soil Science Society America, Madison, WI, 295–315.
Perry, H. R., Green, W. D., and Maloney, O. J. (1999). Perry’s chemical engineers’ handbook, 7th Ed., McGraw Hill, New York.
Pusch, R. (2008). Geological storage of radioactive waste, Springer, Berlin.
Rao, S. M. (2006). “Identification and classification of expansive soils.” Expansive soils: Recent advances in characterization and treatment, Rawas, A. A., and Goosen, M. F. A., eds., Taylor and Francis, London, 15–224.
Riebe, B., Dultz, S., and Bunnenberg, C. (2005). “Temperature effects on iodine adsorption on organo-clay minerals. I. Influence of pretreatment and adsorption temperature.” Appl. Clay Sci.ACLSER, 28(1–4), 9–16.
Sazarashi, M., Ikeda, Y., Seki, R., and Yoshikawa, H. (1994). “Adsorption of ions on minerals for waste management.” J. Nucl. Sci. Technol.JNSTAX, 31(6), 620–622.
Schmett, G. T. (2005). “Immobilization of fission iodine by reaction with fullerene containing carbon compounds or insoluble natural organic matter.” M.Sc. dissertation, Graduate College, Univ. of Nevada, Las Vegas.
Toyohara, M., et al. (2000). “Iodine sorption onto mixed solid alumina cement and calcium compounds.” J. Nucl. Sci. Technol.JNSTAX, 37(11), 970–978.
van Olphen, H. (1963). An introduction to clay colloid chemistry, Wiley, New York.
Yukselen, Y., and Kaya, A. (2003). “Zeta potential of kaolinite in the presence of alkali, alkaline earth and hydrolyzable metal ions.” Water Soil Air PollutionWAPLAC, 145(1), 155–168.
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© 2012. American Society of Civil Engineers.
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Received: Oct 15, 2010
Accepted: Jun 29, 2011
Published online: Jul 1, 2011
Published in print: Jul 1, 2012
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