A method for estimation of surface tension was prepared within the MSc.-thesis of Eugene Olivier. A publication is under preparation.
Estimation of Pure Component Properties, Part 6: Estimation of the Surface Tension of Non-Electrolyte Organic Liquids via Group Contributions
Eugene Oliviera, Jürgen Rareya,b,* , Deresh Ramjugernatha
aThermodynamics Research Unit, School of Chemical Engineering, University of Kwa-Zulu Natal, Durban 4041, RSA
bIndustrial Chemistry, Carl von Ossietzky University Oldenburg, 26111 Oldenburg, FRG
*(corresponding author, tel.: +49 441 798 3846, fax: +49 441 798 3330, email: Juergen@Rarey.Net)
A new group contribution method for the prediction of pure component liquid surface tension has been developed. The method is an extension of the pure component property estimation techniques that we have developed for normal boiling points, critical property data, vapor pressures, viscosities and thermal conductivity of saturated liquids. Predictions can be made from simply having knowledge of the molecular structure of the compound. In addition, the structural group definitions for the method are identical to those proposed by Moller et al. for estimation of saturated vapor pressures. Structural groups were defined in a standardized form and fragmentation of the molecular structures was performed by an automatic procedure to eliminate any arbitrary assumptions. The new method is based on surface tension data for more than 1600 components. Results of the new method are compared to several other estimation methods published in literature and are found to be significantly better. A relative mean deviation in surface tension of 2.90% was observed for a common set of 662 components (12139 data points). By comparison, the Zuo and Stenby method, the best literature method in our benchmarking exercise produced a relative mean deviation of 3.75%. The range of the method is usually from the triple or melting point to the critical point. In case the critical temperature is known, this can be used in the model to enforce the correct value of zero at this temperature.