The Applicability of the Pseudolattice Approach for the Surface Tension of Ionic Liquid Solutions

Document Type : Research Article


1 Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, I.R. IRAN

2 Department of Chemistry, Marvdasht Branch, Islamic Azad University, Marvdasht, I.R. IRAN


Recently, the pseudo lattice theory has been used to derive a simple linear correlation for the prediction of the surface tension of pure ionic liquids and their mixtures. That linear equation includes the parameters of coulomb interactions and the short-range interaction between the ions. In this work, a new correlation was derived for the solutions of ionic liquids in molecular solvents. The obtained correlation, predicts that the difference between the experimental surface tension and an approximated surface tension without including ion-solvent interaction, ( ) is a function of -5/3 order of molar volume.  can be calculated by using thermophysical experimental data. The linearity of the plots of  versus V-5/3 for mixtures of ionic liquids and solvents (alcohols and water) confirms the applicability of the pseudo lattice theory for these systems. The slope of the obtained lines, Bmix, is a measure of ion-solvent interaction and is independent of the temperature and mole fraction. Finally, an empirical linear relationship between Bmix and pure ionic liquid properties was extracted for each solvent. The equation of the last linear correlation is valuable for approximating and consequently, the surface tension of solutions at a varied range of temperatures and mole fractions.


Main Subjects

[1] Holbrey J.D., Reichert W.M., Reddy R.G., Rogers R.D., “Ionic Liquids as Green Solvents: Progress and Prospects”, ACS Symposium Series, American Chemical Society, Washington, DC. 856: 121-133 (2003).
[2] Law G., Watson P. R. Surface Tension Measurements Of N-Alkylimidazolium Ionic Liquids, Langmuir, 17(20): 6138-6141(2001).
[3] Kolbeck C., Lehmann J., Lovelock K.R.J., Cremer T., Paape N., Wasserscheid P., Steinruck H.P., Density and Surface Tension of Ionic Liquids, The Journal of Physical Chemistry B, 114(51): 17025-17036(2010).
[4] Tariq M., Freire M.G., Saramago B., Coutinho J.A., Lopes J.N.C., Rebelo L.P.N., Surface Tension of Ionic Liquids and Ionic Liquid Solutions,  Chemical Society Reviews, 41(2):829-868(2012).
[5] Oliveira M.B., Dominguez-Perez M., Cabeza O., Lopes-da-Silva J.A., Freire M.G., Coutinho J.A.P., Surface Tensions of Binary Mixtures of Ionic Liquids with Bis (Trifluoromethylsulfonyl) Imide as the Common Anion, The Journal of Chemical Thermodynamics, 64: 22-27(2013).
[6] Oliveira M.B., Domínguez-Pérez M., Freire M.G., Llovell F., Cabeza O., Lopes-da-Silva J.A., Coutinho J.A.P., Surface Tension of Binary Mixtures of 1-alkyl-3-methylimidazolium Bis (trifluoromethylsulfonyl) Imide Ionic Liquids: Experimental Measurements and Soft-SAFT Modeling. The Journal of Physical Chemistry B, 116(40): 12133-12141(2012).
[7] Ghatee M.H., Zolghadr A.R., Surface Tension Measurements of Imidazolium-Based Ionic Liquids at Liquid–Vapor Equilibrium, Fluid Phase Equilibria, 263(2): 168-175 (2008).
[8] Domańska U., Pobudkowska A., Rogalski M., Surface Tension of Binary Mixtures of Imidazolium and Ammonium Based Ionic Liquids with Alcohols, or Water: Cation, Anion Effect, Journal of Colloid and Interface Science, 322(1): 342-350(2008).
[9] Abe H.,  Murata K., Ki Yokawa S., Yoshimura Y. Surface Tension Anomalies in Room Temperature Ionic Liquids-Acetone Solutions, Chemical Physics Letters. 699: 275-278 (2018).
[10] Bahe L.W., Structure in Concentrated Solutions of Electrolytes. Field Dielectric Gradient Forces and Energies, The Journal of Physical Chemistry, 76(7): 1062-1071 (1972).
[11] Varela L.M., Carrete J., García M., Rodríguez J.R., Gallego L.J., Turmine M., Cabeza O., Pseudolattice Theory of Ionic Liquids. in Ionic Liquids, Intech. Open. (2011).
[12] Debye P., Huckel E., The Theory of Electrolytes I. the Lowering of the Freezing Point and Related Occurrences, Physikalische Zeitschrift, 24:185-206 (1923).
[13] Varela L.M., Montaña, Turmine J.C.M., Cabeza O., Pseudolattice Theory of the Surface Tension of Ionic Liquid Water Mixtures, The Journal of Physical Chemistry B. 113(37): 12500 (2009).
[14] Chagnes A., Carré B., Willmann P., Lemordant D., Modeling Viscosity and Conductivity of Lithium Salts in γ-butyrolactone. Journal of Power Sources, 109(1): 203-213 (2002).
[15] Chagnes A., Nicolis S., Carré B., Willmann P., Lemordant D., Ion–Dipole Interactions in Concentrated Organic Electrolytes. Chem. Phys. Chem., 4(6): 559-566 (2003).
[16] Moggia E., Osmotic Coefficients of Electrolyte Solutions, The Journal of Physical Chemistry B, 112(4): 1212-1217(2008).
[17] Moggia E., Bianco B., Mean Activity Coefficient of Electrolyte Solutions, The Journal of Physical Chemistry B, 111(12): 3183-3191(2007).
[19] Arjmand F., Aghaie H., Bahadori M., Zare K.,
Surface Tension Investigation of Ionic Liquids by Using the Pseudolattice Theory, Journal of Molecular Liquids, 277: 80-83(2019).
[20] Varela L.M., Garcia M., Sarmiento F., Attwood D., Mosquera V., Pseudolattice Theory of Strong Electrolyte Solutions, The Journal of Chemical Physics, 107(16): 6415-6419 (1997).
[21] Ozaki H., Kuratani K., Sano H., Kiyobayashi T., A Monte-Carlo Simulation of Ionic Conductivity and Viscosity of Highly Concentrated Electrolytes Based on a Pseudolattice Model, Journal Chemical Physics. 147(3): 034904 (2017).
[22] Shuttleworth R., The Surface Tension of Solids, Proceedings of the Physical Society. Section A, 63(5): 444 (1950).
[23] Vargaftik N.B., Vinogradov Y.K., Yargin V.S., “Handbook of Physical Properties of Liquids and Gases Pure Substances and Mixtures”, 3rd ed, Begell House, Inc., New York. (1996).
[26] Clough M.T., Crick C.R., Gräsvik J., Hunt P.A., Niedermeyer H., Welton T., Whitaker O.P., A Physiochemical Investigation of Ionic Liquid Mixtures, Chem. Sci., 6: 1101-1114 (2015).
[27] Chakraborty M., Barik S., Mahapatra A., Sarkar M., Binary Mixtures of Ionic Liquids: Ideal, Non- Ideal, or Quasi-Ideal? J. Chem. Phys., 154: 224507-14 (2021).
[28] Kumar A., Singh T., Gardas R. L., Coutinho J.A.P., Non-Ideal Behaviour of A Room Temperature Ionic Liquid in an Alkoxyethanol or Poly Ethers at T = (298.15 to 318.15) K, J. Chem. Thermodynamics, 40: 32–39 (2008).
[29] Singh T., Kumar A., Kaur M., Kaur G., Kumar H., Non-ideal Behaviour of Imidazolium Based Room Temperature Ionic Liquids in Ethylene Glycol at T = (298.15 to 318.15) K, J. Chem. Thermodynamics, 41: 717–723 (2009).