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The effect of uncertainties in stability constants on speciation diagrams

Published online by Cambridge University Press:  11 February 2011

Arvid Ödegaard-Jensen ,
Christian Ekberg  and
Gunther Meinrath
Arvid Ödegaard-Jensen
Affiliation:
Dept. Nuclear Chemistry, Chalmers University of Technology, S-412 96 Göteborg, Sweden.
Christian Ekberg
Affiliation:
Dept. Nuclear Chemistry, Chalmers University of Technology, S-412 96 Göteborg, Sweden.
Gunther Meinrath
Affiliation:
RER Consultants Passau, Schieβstattweg 3a, D-94032 Passau, Germany Technical University Mining Academy Freiberg, Institute of Geology, D-09596 Freiberg, Germany
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Abstract

Speciation calculations are one of the more common ways to describe a chemical system. Speciation diagrams is a convenient way to display such calculations and may also be the basis on which experiments in neighbouring fields of interest, such as sorption are based. In earlier days only very simple problems could be described, e.g. hydroxide species dominance diagrams versus pH. With the aid of computers, however, more complicated systems such as groundwater chemistry may be used. However, as the complexity increase, so does the effect of uncertainties. In this paper we focus on the effect uncertainties in stability constants may have on speciation calculations. The common belief is that the curves will be replaced by narrow bands, while the truth is far from that. In many cases one or several species cover the entire region between 0 and 100%.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 757: Symposium II – Scientific Basis for Nuclear Waste Management XXVI , 2002 , II3.35
Copyright
Copyright © Materials Research Society 2003

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References

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