Original scientific paper
https://doi.org/10.5599/jese.228
Ruthenium redox equilibria 2. Thermodynamic analysis of disproportionation and comproportionation conditions
Igor Povar
; Institute of Chemistry of the Academy of Sciences of Moldova, 3 Academiei str., MD 2028, Chisinau, Moldova
Oxana Spinu
; Institute of Chemistry of the Academy of Sciences of Moldova, 3 Academiei str., MD 2028, Chisinau, Moldova
Abstract
The key property of Frost diagram has been confirmed using thermodynamic and linear algebra methods. On the basis of the thermodynamic data, the areas of thermodynamic stability of ruthenium species of different valence states as a function of pH for each degree of oxidation have been determined. Subsequently, based on the diagrams calculated for several values of pH, a narrow ΔpH value is determined, in which the dismutation of appropriate form takes place. Based on thermodynamic analysis, the exact value of the beginning of disproportionation (or comproportionation) is found. Finally, the developed revised Frost diagrams of ruthenium heterogeneous chemical and redox equilibria, as a function of pH and the total concentration of metal ion in solution, have been built.
Keywords
Disproportionation and comproportionation equilibria; Revised Frost diagram; Reduced Gibbs energy of half reaction of oxidation; Ruthenium soluble and insoluble species
Hrčak ID:
156457
URI
Publication date:
21.4.2016.
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