Hostname: page-component-586b7cd67f-rdxmf Total loading time: 0 Render date: 2024-11-24T18:40:25.707Z Has data issue: false hasContentIssue false
  • English
  • Français

Experimental Study and Modeling of Uranium (VI) Sorption onto a Spanish Smectite

Published online by Cambridge University Press:  01 February 2011

Tiziana Missana ,
Ursula Alonso ,
Miguel Garcia-Gutierrez ,
Nairoby Albarran  and
Trinidad Lopez
Tiziana Missana
Affiliation:
[email protected], CIEMAT, Medioambiente, MADRID, Spain
Ursula Alonso
Affiliation:
[email protected]@gmail.com, CIEMAT, Medioambiente, MADRID, Spain
Miguel Garcia-Gutierrez
Affiliation:
[email protected], CIEMAT, Medioambiente, MADRID, Spain
Nairoby Albarran
Affiliation:
[email protected], CIEMAT, Medioambiente, MADRID, Spain
Trinidad Lopez
Affiliation:
[email protected], CIEMAT, Medioambiente, MADRID, Spain
Get access

Abstract

Adsorption of uranium onto a Spanish smectite was studied, analyzing the effects of the most important parameters such as pH, ionic strength, radionuclide concentration and solid to liquid ratio. Batch sorption studies, in anoxic conditions under N2 atmosphere, were carried out on the bentonite previously purified and converted into the homoionic Na-form. In the sorption edges, two regions could be clearly distinguished. At pH lower than 5, sorption depended strongly on the ionic strength, possibly indicating the predominance of the uranyl ionic exchange process. At higher pH, sorption did not depend on the ionic strength but only on pH. The sorption behavior in this region suggested the predominance of a surface complexation mechanism. Sorption isotherms showed a non linear behavior in the concentration range used. Sorption data were interpreted using a non electrostatic standard model combining surface complexation, with the weak and strong SOH sites of the clay, and ionic exchange. The acid – base properties of the weak SOH sites were determined by potentiometric titrations. The model used was able to reproduce, in a very satisfactory way, all the data in a wide range of experimental conditions.

Keywords

adsorptionUwaste management
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1124: Symposium Q – Scientific Basis for Nuclear Waste Management XXXII , 2008 , 1124-Q07-05
Copyright
Copyright © Materials Research Society 2009

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. Missana, T., Garcia-Gutierrez, M., Fernandez, V. and Gil, P., Application of mechanistic models for the interpretation of radionuclides sorption in clays. Part 1. CIEMAT/DIAE/54610/03, (Madrid-Spain, 2002), pp. 1–47.Google Scholar
2. Missana, T., Alonso, U., Garcia-Gutierrez, M., Albarran, N. and Lopez, T.. Experimental study and modeling of europium adsorption onto smectite clay colloids. CIEMAT /DMA /2G102 /05/08 (Madrid-Spain, 2008), pp. 1–28.Google Scholar
3. Missana, T., Alonso, U. and Garcia-Gutierrez, M., J. of Colloid Interface Sci., Submitted.Google Scholar
4. Missana, T. and Garcia-Gutierrez, M., Phys. Chem. Earth, 32, 559 (2007).Google Scholar
5. Turner, G.D., Zachara, J.M., McKinley, J.P. and Smith, S.C., Geochim. Cosmochim. Acta, 60(18), 3399 (1996).Google Scholar
6. Kowal-Fouchard, A., Drot, R., Simoni, E. and Ehrhardt, J.J., Environ. Sci. Technol., 38, 1399 (2004).Google Scholar
7. Fernandez, A. M., Baeyens, B., Bradbury, M., Rivas, P., Phys. Chem. Earth, 29(1), 105 (2004).Google Scholar
8. Gaines, G.I. and Thomas, H.C., J. Chem. Phys., 21, 714 (1953).Google Scholar
9. Bradbury, M.H. and Baeyens, B., Sorption by Cation Exchange: Incorporation of a cation exchange model into geochemical computer codes. PSI Bericht 94–07 (Villingen-Switzerland, 1994).Google Scholar
10. Grenthe, I., Chemical thermodynamics of uranium, North Holland Elsevier (1992).Google Scholar
11. van der Lee, J. and DeWindt, L., CHESS tutorial and cookbook. Technical Report École des Mines, LHM/RD/99/05 (Paris-France, 1999).Google Scholar