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On the Problem of Consistency of Chemical Thermodynamic Data Bases

Published online by Cambridge University Press:  28 February 2011

Hans Wanner
Hans Wanner*
Affiliation:
OECD Nuclear Energy Agency, Data Bank 91191 Gif-sur-Yvette, France
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Abstract

The geochemical modelling in support of the performance assessment of radioactive waste disposal systems calls for a large number of chemical thermodynamic data. For realistic modelling it is essential that the data used are fully consistent. The verification of consistency of existing data bases is complicated by the fact that it requires the knowledge of a considerable amount of primary information to ensure:

  1. 1. Consistency with the fundamental laws of thermodynamics

  2. 2. Consistency within a chemical model

  3. 3. Consistency with auxiliary data

  4. 4. Consistency in the data correction procedures

This paper includes selected examples for each of the four items to visualize the problems. It should be noted that there are numerous other systems that could serve as examples as well, and the range of cases reported here is far from being exhaustive.

Realistic geochemical modelling depends not only on the quality of the data base, but also on the quality of the chemical model used. For the establishment of a chemical model, additional information is needed that is not contained in thermodynamic data bases.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 212: Symposium P – Scientific Basis for Nuclear Waste Management XIV , 1990 , 815
Copyright
Copyright © Materials Research Society 1991

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References

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