Abstract
The standard free energy of surfactant adsorption represents the work of transfer of a surfactant molecule from the bulk of solution to an infinitely diluted adsorption layer. This quantity can be determined by non-linear fits of surface-tension isotherms with the help of a theoretical model of adsorption. Here, the models of Frumkin, van der Waals and Helfand-Frisch-Lebowitz are applied, and the results are compared. Irrespective of the differences between these models, they give close values for the standard free energy. The results from the theoretical approach are compared with those from the most popular empirical approach. The latter gives values of the standard free energy, which are considerably different from the respective true values, with c.a. 10 kJ/mol for nonionic surfactants, and with c.a. 20 kJ/mol for ionic surfactants. These differences are due to contributions from interactions between the molecules in dense adsorption layers. It is concluded that the true values of the standard free energy can be determined with the help of an appropriate theoretical model. For the processed sets of data, the van der Waals model gives the best results, especially for the determination of the standard adsorption enthalpy and entropy from the temperature dependence of surface tension. The results can be useful for the development of a unified approach to the thermodynamic characterization of surfactants.
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References
Rusanov, A.I., Phasengleichgewichte und Grenzflächenerscheinungen, Berlin: Akademie Verlag, 1978.
Couper, A., in Surfactants, Tadros, Th.F., Ed., London: Academic Press, 1984.
Durbut, P., in Handbook of Detergents, Part A: Properties, Broze, G., Ed., New York: Marcel Dekker, 1999.
Rosen, M.J., Surfactants and Interfacial Phenomena, 3 rd Edition, New York: Wiley-Interscience, 2004.
Davies, J.T. and Rideal, E.K., Interfacial Phenomena, New York: Academic Press, 1963.
Kumpulainen, A.J., Persson, C.M., and Eriksson, J.C., Langmuir, 2004, vol. 20, p. 10935.
Danov, K.D., Kralchevsky, P.A., Ananthapadmanabhan, K.P., and Lips, A., J. Colloid Interface Sci., 2006, vol. 300. p. 809.
Rosen, M.J. and Aronson, S., Colloids Surfaces, 1981, vol. 3, p. 201.
Miller, R., Fainerman, V.B., and Möhwald, H., J. Surfactants Deterg., 2002, vol. 5, p. 281.
Kolev, V.L., Danov, K.D., Kralchevsky, P.A., Broze, G., and Mehreteab, A., Langmuir, 2002, vol. 18, p. 9106.
Valkovska, D.S., Shearman, G.S., Bain, C.D., Darton, R.C., and Eastoe, J., Langmuir, 2004, vol. 20, p. 4436.
Raut, J.S., Akella, S., Singh, A.K., and Naik, V.M., Langmuir, 2009, vol. 25, p. 4829.
Ivanov, I.B., Danov, K.D., Dimitrova, D., Boyanov, M., Ananthapadmanabhan, K.P., and Lips, A., Colloids Surf. A, 2010, vol. 354, p. 118.
Ritacco, H.A., Ortega, F., Rubio, R.G., Ivanova, N., and Starov, V.M., Colloids Surf. A, 2010, vol. 365, p. 199.
Fainerman, V.B., Aksenenko, E.V., Petkov, J.T., and Miller, R., Colloids Surf. A, 2011, vol. 385, p. 139.
Kalinin, V.V. and Radke, C.J., Colloids Surf. A, 1996, vol. 114, p. 337.
Warszyn-ski, P., Barzyk, W., Lunkenheimer, K., and Fruhner, H., J. Phys. Chem. B, 1998, vol. 102, p. 10948.
Kralchevsky, P.A., Danov, K.D., Broze G., and Mehreteab, A., Langmuir, 1999, vol. 15, p. 2351.
Kralchevsky, P.A., Danov, K.D., Kolev, V.L., Broze, G., and Mehreteab, A., Langmuir, 2003, vol. 19, p. 5004.
Danov, K.D., Kralchevska, S.D., Kralchevsky, P.A., Broze, G., and Mehreteab, A., Langmuir, 2003, vol. 19, p. 5019.
Shchukin, E.D., Pertsov, A.V., Amelina, E.A., and Zelenev, A.S., Colloid and Surface Chemistry, Amsterdam: Elsevier, 2001.
Wei, Y. and Latour, R.A., Langmuir, 2008, vol. 24, p. 6721.
Liu, Y., J. Chem. Eng. Data, 2009, vol. 54, p. 1981.
Langmuir, I., J. Am. Chem. Soc., 1917, vol. 39, 1848.
Adamson, A.W. and Gast, A.P., Physical Chemistry of Surfaces, 6 th Edition, New York: Wiley-Interscience, 1997.
Posner, A.M., Anderson, J.R., and Alexander, A.E., J. Colloid Sci., 1952, vol. 7, p. 623.
Gibbs, J.W., The Scientific Papers of J.W. Gibbs, Vol. 1, New York: Dover, 1961.
Jan-czuk, B., Brugue, J.M., Gonzáles-Martín, M.L., and Dorado-Calasanz, C., Langmuir, 1995, vol. 11, p. 4515.
El Ghzaoui, A., Fabrègue, E., Cassanas, G., Fulconis, J.M., and Delagrange, J., Colloid Polym. Sci., 2000, vol. 278, p. 321.
Hill, T.L., An Introduction to Statistical Thermodynamics, New York: Dover, 1987.
Kralchevsky, P.A., Danov, K.D., and Denkov, N.D., in Handbook of Surface and Colloid Chemistry, 3 rd Edition, Birdi, K.S., Ed., New York: Taylor & Francis, 2009, p. 197.
Helfand, E., Frisch, H.L., and Lebowitz, J.L., J. Chem. Phys., 1961, vol. 34, p. 1037.
Stanimirova, R., Marinova, K., Tcholakova, S., Denkov, N.D., Stoyanov, S., and Pelan, E., Langmuir, 2011, vol. 27, p. 12486.
Lee, H., Venable, R.M., MacKerell, A.D., and Pastor, R.W., Biophys. J., 2008, vol. 95, p. 1590.
Lunkenheimer, K., Barzyk, W., Hirte, R., and Rudert, R., Langmuir, 2003, vol. 19, p. 6140.
Christov, N.C., Danov, K.D., Kralchevsky, P.A., Ananthapadmanabhan, K.P., and Lips, A., Langmuir, 2006, vol. 22, p. 7528.
Danov, K.D., Kralchevska, S.D., Kralchevsky, P.A., Ananthapadmanabhan, K.P., and Lips, A., Langmuir, 2004, vol. 20, p. 5445.
Rusanov, A.I., J. Chem. Phys., 2003, vol. 118, p. 10157.
Rusanov, A.I., J. Chem. Phys., 2003, vol. 119, p. 10268.
Rusanov, A.I., J. Chem. Phys., 2004, vol. 121, p. 1873.
Rusanov, A.I., J. Chem. Phys., 2004, vol. 120, p. 10736.
Fainerman, V.B. and Lucassen-Reynders, E.H., Adv. Colloid Interface Sci., 2002, vol. 96, p. 295.
Stern, O., Ztschr. Elektrochem., 1924, vol. 30, p. 508.
Gouy, G., J. Phys. Radium, 1910, vol. 9, p. 457.
Gurkov, T.D., Dimitrova, D.T., Marinova, K.G., Bilke-Crause, C., Gerber, C., and Ivanov, I.B., Colloids Surf. A, 2005, vol. 261, p. 29.
Danov, K.D., Kolev, V.L., Kralchevsky, P.A., Broze G., and Mehreteab, A., Langmuir, 2000, vol. 16, p. 2942.
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The article is dedicated to Academician Anatoly I. Rusanov on the occasion of his 80th birthday.
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Danov, K.D., Kralchevsky, P.A. The standard free energy of surfactant adsorption at air/water and oil/water interfaces: Theoretical vs. empirical approaches. Colloid J 74, 172–185 (2012). https://doi.org/10.1134/S1061933X12020032
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DOI: https://doi.org/10.1134/S1061933X12020032