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Diffusion of Uranium in Compacted Sodium Bentonite

Published online by Cambridge University Press:  01 January 1992

Arto Muurinen
Affiliation:
Technical Research Centre of Finland, Reactor Laboratory, P.O. Box 200, SF-02151 Espoo, Finland
Kaija Ollila
Affiliation:
Technical Research Centre of Finland, Reactor Laboratory, P.O. Box 200, SF-02151 Espoo, Finland
Jarmo Lehikoinen
Affiliation:
Technical Research Centre of Finland, Reactor Laboratory, P.O. Box 200, SF-02151 Espoo, Finland
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Abstract

In this study the diffusion of uranium dissolved from uranium oxide fuel was studied experimentally in compacted sodium bentonite (Wyoming bentonite MX-80). The parameters varied in the study were the density of bentonite, the salt content of the solution and the redox conditions. In the studies with non-saline water of total dissolved solids about 300 ppm, uranium was both in aerobic and anaerobic experiments as anionic complexes and followed the anionic diffusion mechanism. Anion exclusion decreased effective diffusion coefficients, especially in more dense samples. In the studies with saline water of total dissolves solids about 35000 ppm, uranium appeared in the aerobic experiments probably as cationic complexes and followed the cationic diffusion mechanism. Uranium in the saline, anaerobic experiment was probably U(OH)4 and followed the diffusion mechanism of neutral species.

Type
Research Article
Copyright
Copyright © Materials Research Society 1993

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References

REFERENCES

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