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Geopolymers for the Immobilization of Radioactive Waste

Published online by Cambridge University Press:  17 March 2011

D S Perera ,
M G Blackford ,
E R Vance ,
J V Hanna ,
K S Finnie  and
C L Nicholson
D S Perera
Affiliation:
Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234, Australia
M G Blackford
Affiliation:
Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234, Australia
E R Vance
Affiliation:
Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234, Australia
J V Hanna
Affiliation:
Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234, Australia
K S Finnie
Affiliation:
Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234, Australia
C L Nicholson
Affiliation:
Industrial Research Ltd., PO Box 31-310, Lower Hutt, New Zealand
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Abstract

Geopolymers are made by adding aluminosilicates to concentrated alkali solutions for dissolution and subsequent polymerization to form a solid. They are amorphous to semicrystalline three dimensional aluminosilicate networks. Although they have been used in several applications their widespread use is restricted due to lack of long term durability studies and detailed scientific understanding. Three important tools for the study of geopolymers are transmission electron microscopy (TEM), solid state magic angle spinning nuclear magnetic resonance (MAS NMR) and infra red (IR) spectroscopy.

Cs and Sr are two of the most difficult radionuclides to immobilize and are therefore suitable elements to study in assessing geopolymers as matrices for immobilization of radioactive wastes. In this study Cs or Sr was added to geopolymer samples prepared using fly ash precursors. A commercial metakaolinite geopolymer was studied for comparison.

The geopolymers were mainly amorphous as shown by TEM, whether they were made from fly ash or metakaolinite. In the fly ash geopolymer, Cs preferentially inhabited the amorphous phase over the minor crystalline phases, whereas Sr was shared in both. The MAS NMR showed that Cs is held mostly in the geopolymer structure for both fly ash and metakaolinite geopolymers. The IR spectra showed a slight shift in antisymmetric Si-O-Al stretch band to a lower wavenumber for the fly ash geopolymer, which implies that more Al is incorporated in this geopolymer structure than in the metakaolinite geopolymer.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 824: Symposium CC – Scientific Basis for Nuclear Waste Management XXVIII , 2004 , CC8.35
Copyright
Copyright © Materials Research Society 2004

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References

1. Davidovits, J., J. Therm. Anal., 37, 1633 (1991).Google Scholar
2. Davidovits, J. and Comrie, D., in Geopolymer '88, First European Conference on Soft Mineralogy, Conference Proceedings, 1-3 June, Compiegne, France, edited by. Davidovits, J. and Orlinski, J., (Geopolymer Institute, Saint-Quentin, France, 1988) pp.125–134.Google Scholar
3. Perera, D S, Vance, E R, Aly, Z, Finnie, K S, Hanna, J V, Nicholson, C L, Trautman, R L and Stewart, M W A, in Proceedings of the ICEM'03, 9th International Conference on Radioactive Waste Management and Environmental Remediation, Sept 21-25, 2003 (Laser Options Inc., Tucson, USA, 2004), CD, paper no. 4589.Google Scholar
4. Perera, D S, Nicholson, C L, Blackford, M G, Fletcher, R A, Trautman, R L, J. Jpn. Ceram. Soc., 2004 (in press).Google Scholar
5. Barbosa, V. F. F., MacKenzie, K. J. D. and Thaumaturgo, C., Int. J. Inorg. Mat., 2, 309 (2000).Google Scholar
6. Davidovits, J., in Second International Conference, Geopolymere '99, June 30- July 2, 1999, edited by Davidovits, J, Davidovits, R. and James, C., (Geopolymer Institute, Saint-Quentin, France, 1999), pp. 9–40.Google Scholar
7.Unpublished work, 2003, Australian Nuclear Science and Technology Organisation, Sydney, Australia.Google Scholar