Complex-forming equilibria in isotachophoresis : VI. simulation of isotachophoretic equilibria of lathanoids and determination mobilities and stability constants of acetate and β-hydroxyisobutyrate complexes

doi:10.1016/S0021-9673(01)92760-8

Journal of Chromatography A

Volume 312, 1984, Pages 11-29

https://doi.org/10.1016/S0021-9673(01)92760-8 Get rights and content

Abstract

The istachophoretic separation of fourteen lanthanoids (Ln) was studied using three difeerent electrolyte systems, viz., acetic acid (Ac), β-hydroxyisobutyric acid (HIB) and their mixture, as the complexing agent. A computational procedure based on the least-squares technique was used for the determination of the absolute mobilities of LnAc, LnHIB and Ln(HIB)Ac complexes from the qualitative index R_E. The stability constants of Ln(HIB)Ac were also determined. Using the determ constants, the isotachophoretic separation of lanthanoids could be explained by the differences in the effective mobilities accompanied by the different abundances of multi-coordinated complexes.

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Complex-forming equilibria in isotachophoresis : VI. simulation of isotachophoretic equilibria of lathanoids and determination mobilities and stability constants of acetate and β-hydroxyisobutyrate complexes

Abstract

J. Chromatogr.

J. Chromatogr.

J. Chromatogr.

J. Chromatogr.

J. Amer. Chem. Soc.

J. Amer. Chem. Soc.