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Abraham Model Correlations for Triethylene Glycol Solvent Derived from Infinite Dilution Activity Coefficient, Partition Coefficient and Solubility Data Measured at 298.15 K

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Abstract

A gas chromatographic headspace analysis method was used to experimentally determine gas-to-liquid partition coefficients and infinite dilution activity coefficients for 29 liquid organic solutes dissolved in triethylene glycol at 298.15 K. Solubilities were also determined at 298.15 K for 23 crystalline nonelectrolyte organic compounds in triethylene glycol based on spectroscopic absorbance measurements. The experimental results of the headspace chromatographic and spectroscopic solubility measurements were converted to gas-to-triethylene glycol and water-to-triethylene glycol partition coefficients, and molar solubility ratios using standard thermodynamic relationships. Expressions were derived for solute transfer into triethylene glycol by combining our measured experimental values with published literature data. Mathematical correlations based on the Abraham model describe the observed partition coefficient and solubility data to within 0.16 log10 units (or less).

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Acknowledgements

The work of Igor Sedov and Timur Magsumov was performed according to the Russian Government Program of Competitive Growth of Kazan Federal University. Maribel Barrera thanks the University of North Texas and the U.S. Department of Education for support provided under the Ronald E. McNair Postbaccalaureate Achievement Program.

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Authors and Affiliations

  1. Department of Chemistry, Kazan Federal University, Kremlevskaya 18, Kazan, Russia, 420008

    Igor A. Sedov & Timur I. Magsumov

  2. Department of Chemistry, University of North Texas, 1155 Union Circle Drive #305070, Denton, TX, 76203, USA

    Erin Hart, Ashley M. Ramirez, Sarah Cheeran, Maribel Barrera, Melissa Y. Horton, Anisha Wadawadigi, Olivia Zha, Xin Y. Tong & William E. Acree Jr.

  3. Department of Chemistry, University College London, 20 Gordon Street, London, WC1H OAJ, UK

    Michael H. Abraham

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  1. Igor A. Sedov
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  2. Timur I. Magsumov
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  11. William E. Acree Jr.
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Glossary of Symbols and Definitions

a k

Solvent property in Eq. 2 of the Abraham model reflecting the ability of the organic solvent to act as an H-bond acceptor

a p

Solvent property in Eq. 1 of the Abraham model reflecting the ability of the organic solvent to act as an H-bond acceptor

b k

Solvent property in Eq. 2 of the Abraham model reflecting the ability of the organic solvent to act as an H-bond donor

b p

Solvent property in Eq. 2 of the Abraham model reflecting the ability of the organic solvent to act as an H-bond donor

c k

Constant in Eq. 1 of the Abraham model

c p

Constant in Eq. 1 of the Abraham model

e k

Solvent property in Eq. 2 of the Abraham model reflecting the ability of the organic solvent to interact with dissolved solutes by electron lone pair interactions

e p

Solvent property in Eq. 1 of the Abraham model reflecting the ability of the organic solvent to interact with dissolved solutes by electron lone pair interactions

l k

Solvent property in Eq. 2 of the Abraham model describing the dispersion forces/cavity formation

p osolute

The vapor pressure of the solute at 298.15 K

s k

Solvent property in Eq. 2 of the Abraham model that reflects the dipolarity/polarizability of the organic solvent

s p

Solvent property in Eq. 1 of the Abraham model that reflects the dipolarity/polarizability of the organic solvent

v p

Solvent property in Eq. 1 of the Abraham model describing the dispersion forces/cavity formation

A

Abraham model solute descriptor corresponding to the overall or total hydrogen-bond acidity

B

Abraham model solute descriptor corresponding to the overall or total hydrogen-bond basicity

C S,gas

Molar gas phase concentration of the solute used in calculating the solubility ratio for Eq. 2 of the Abraham model

C S,organic

Molar solubility of the solute in the organic solvent

C S,water

Molar solubility of the solute in water

E

Solute descriptor corresponding to the solute excess molar refractivity in units of (cm3·mol–1)/10

Δsolv G

The Gibbs energy of solvation of the solute

K

The solute’s gas-to-organic solvent partition coefficient

K w

The solute’s gas-to-water partition coefficient at 298.15 K

L

The logarithm of the gas-to-hexadecane partition coefficient at 298 K

P

The solute’s water-to-organic solvent partition coefficient

R

The universal gas constant

S

Abraham model solute descript that quantifies the dipolarity/-polarizability of the solute

T

The system temperature in Kelvin

V

Refers to the McGowan volume in units of (cm3·mol–1)/10

V solute

The molar volume of the solute

V solvent

The molar volume of the solvent at 298.15 K

X S,organic(exp.)

The experimental mole fraction solubility of the solute in the organic solvent

γ ∞

The infinite dilution activity coefficient of the solute

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Sedov, I.A., Magsumov, T.I., Hart, E. et al. Abraham Model Correlations for Triethylene Glycol Solvent Derived from Infinite Dilution Activity Coefficient, Partition Coefficient and Solubility Data Measured at 298.15 K. J Solution Chem 46, 2249–2267 (2017). https://doi.org/10.1007/s10953-017-0692-x

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