Hostname: page-component-848d4c4894-tn8tq Total loading time: 0 Render date: 2024-06-16T18:50:25.197Z Has data issue: false hasContentIssue false
  • English
  • Français

Measurements of Metal Adsorption in Oxide-Clay Mixtures: “Competitive-Additivity” Among Mixture Components

Published online by Cambridge University Press:  01 January 1992

V. S. Tripathi ,
M.D. Siegel  and
Z. S. Kooner
V. S. Tripathi
Affiliation:
Environmental and Earth Sciences Institute, McLean, Va 22101
M.D. Siegel
Affiliation:
Geoscience Assessment and Validation Division 6115, Sandia National Laboratories, Albuquerque, NM 87185
Z. S. Kooner
Affiliation:
Dept. of Geology, University of Tennessee, Knoxville, TN 37916
Get access

Abstract

An important question concerning the transport of radionuclides from nuclear waste repositories is whether the adsorption of metals by rocks and soils can be predicted from the properties of the constituent minerals. Attempts by previous researchers to use sorption models based on linear adsorption or weighted "sorptive additivity" have met with limited success. In this study, a “competitive-additivity” model based on surface complexation theory was used to model the pH-dependent adsorption of lead by goethite/Ca-montmorillonite mixtures using complexation constants obtained from single sorbent systems. Measurements of lead adsorption by goethite, Ca-montmorillonite, and goethite-Ca-montmorillonite mixtures (and similar studies of copper and zinc adsorption) demonstrate that the two adsorbents compete for adsorption of metals over wide ranges of pH and concentrations of adsorbents and metals. The adsorption behaviors of the mixtures are determined by the relative concentrations of the adsorbents and their respective affinities for the adsorbate metal. Particle-particle interactions such as heterocoagulation of the oxide and clay do not appear to be significant for the majority of the adsorption sites in this system.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 294: Symposium V – Scientific Basis for Nuclear Waste Management XVI , 1992 , 791
Copyright
Copyright © Materials Research Society 1993

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. James, R. O. and Leckie, J. O., in Aqueous-Environmental Chemistry of Metals, edited by Rubin, A. (Ann Arbor Science, Ann Arbor, MI, 1974) p. 1.Google Scholar
2. Hochella, M. F. and White, A. F., in Mineral-Water Interface Geochemistry, edited by Hochella, M. F. and White, A. F. (Mineralogical Society of America, Washington, DC, 1990), p. 1.Google Scholar
3. Bolt, G. H. and van Riemsdijk, W. H., in Aquatic Surface Chemistry, edited by Stumm, W. (Wiley, New York, 1987), p. 127.Google Scholar
4. Davis, J. A. and Kent, D. B., in Mineral-Water Interface Geochemistry, edited by Hochella, M. F. and White, A. F. (Mineralogical Society of America, Washington, DC, 1990), p. 177.Google Scholar
5. Dillard, J. G., and Koppelman, M. H., J. Coll. Interf. Sci. 87, 46 (1982).Google Scholar
6. Hayes, K. F., Roe, A. L., Brown, G. E., Hodgson, K. O., Leckie, J. O., and Parks, G.A., Science 238, 783 (1987).Google Scholar
7. Honeyman, B. D., PhD thesis, Stanford University, 1984.Google Scholar
8. Palmer, D. A., Shiao, S.Y., Meyer, R. E., and Wethington, J. A., J. Inorg. Nucl. Chem. 43, 3317 (1981).Google Scholar
9. Di, D. M. Toro, Mahony, J. D., Kirchgraber, P. R., O, A. L.'Byrne, Pasquale, L. R., and Piccirilli, D. C., Environ. Sci. Technol. 20, 55 (1985).Google Scholar
10. Tripathi, V. S., PhD thesis, Stanford University, 1983.Google Scholar
11. Madsen, F .T., in Data Handbook for Clay Minerals and other Non-metallic Minerals, edited by van Olphen, H.. and Fripiat, J. J. (Pergamon Press, Oxford, 1979).Google Scholar
12. Papelis, C., Hayes, K. F., and Leckie, J. O., HYDRAQL: A Program for the Computation of Chemical Equilibrium Composition of Aqueous Batch Systems Including Surface- Complexation Modeling of Ion Adsorption of the Oxide/Solution Interface (Stanford University Technical Report No. 306, 1988).Google Scholar
13. Zachara, J. M., Ainsworth, C. C., Cowan, C. E., and Resch, C. T., Soil Sci. Soc. Am. J. 53, 418 (1989).Google Scholar