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Generation and Characterisation of Colloids of the Near Field / far Field Interface

Published online by Cambridge University Press:  10 February 2011

T. Missana
Affiliation:
CIEMAT, Dpto. Impacto Ambiental de la Energía Avenida Complutense 22, 28040 MADRID (SPAIN)
M. J. Turrero
Affiliation:
CIEMAT, Dpto. Impacto Ambiental de la Energía Avenida Complutense 22, 28040 MADRID (SPAIN)
A. Melon
Affiliation:
CIEMAT, Dpto. Impacto Ambiental de la Energía Avenida Complutense 22, 28040 MADRID (SPAIN)
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Abstract

The generation of bentonite colloids has been investigated by means of column experiments with bentonite compacted at the engineering barrier density and using water flows as low as 0.04 ml/h (≈350 ml/year). Results on generation of bentonite colloids in these “all-bentonite” columns suggested that most of the colloidal material observed in the eluted water is due to erosion of the plug. Therefore new column experiments in which granite and compacted bentonite are in contact have been designed and the effects of the water flow analysed. The physico - chemical characteristics of the colloidal material obtained in the “all-bentonite” and “bentonite plus granite” column experiments have been compared as well as its stability. Results show that bentonite colloids that have been in contact with granite always present a higher negative charge, this indicating that they could be stable in the natural environment.

Type
Research Article
Copyright
Copyright © Materials Research Society 1999

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References

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