Quick
Search: 		  
advanced search
 GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help 
Clays and Clay Minerals Signup for GSW Email News
JOURNAL HOME HELP CONTACT PUBLISHER SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Clays and Clay Minerals; February 2005; v. 53; no. 1; p. 37-44; DOI: 10.1346/CCMN.2005.0530105
© 2005 Clay Minerals Society
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Alba, M. D.
Right arrow Articles by Chain, P.
Right arrow Search for Related Content
GeoRef
Right arrow GeoRef Citation

INTERACTION BETWEEN Lu CATIONS AND 2:1 ALUMINOSILICATES UNDER HYDROTHERMAL TREATMENT

María D. Alba* and Pablo Chain

Institute Ciencia de los Materiales de Sevilla, Departamento de Química Inorgánica, CSIC, Universidad de Sevilla, Avenida Américo Vespucio, s/n 41092 Seville, Spain

* E-mail address of corresponding author: alba{at}icmse.csic.es

Smectites are considered to be an important component in backfill barriers due to their marked swelling and high cation exchange capacity. Both properties are affected considerably when these clays transform under natural conditions. However, we have recently described a chemical interaction between high-activity radionuclide simulators and smectites which could prove to be effective at immobilizing radionuclides definitively. Investigating the efficiency of this mechanism, independent of bentonite ageing, is a challenge. For this purpose, the reactivity shown by a non-expandable layered aluminosilicate, muscovite, has been compared to that shown by an expandable one, beidellite. Both samples were treated hydrothermally with a solution of lutetium nitrate, and the transformations were studied by X-ray diffraction, nuclear magnetic resonance and scanning electron microscopy/energy dispersive X-ray analysis. Lutetium cations react with the silicon framework of both 2:1 layered aluminosilicates under hydrothermal conditions, and new phases, lutetium disilicate, kaolinite, boehmite and natrosilite are generated. The results demonstrate that the efficiency of the chemical mechanism is not determined by the swelling and the cation exchange capacity of 2:1 layered aluminosilicates. Thus, the rare earth disilicate formation might account for the success of the clay barrier, once bentonite has lost its swelling and cation exchange capacity.

Key Words: Bentonite • CEC • Hydrothermal Alteration • Lutetium Cations • Nuclear Waste Barriers • Radionuclide Barriers






JOURNAL HOME HELP CONTACT PUBLISHER SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2008 by Clay Minerals Society