A semi-empirical equation for determining the surface tension of imidazolium-based ionic liquids
Subject Areas : Kinetics and Thermodynamics
1 - Department of Chemistry, Marvdasht Branch, Islamic Azad University, Marvdasht, 7371113119, Iran
Keywords: Ionic liquids, Potential model, Internal pressure, Surface tension. ,
Abstract :
In this research, using appropriate thermodynamic arguments and models, a semi-empirical equation was obtained to calculate the surface tension of imidazolium-based ionic liquids. In the first method used, the Stockmayer potential model was chosen to describe the interaction between particles, and an isothermal thermodynamic equation was extracted from this equation. Using the experimental data of pVT, the parameters of the thermodynamic equation and potential function were obtained. These parameters were used to estimate the internal pressure and pair correlation function of the studied systems. Then, using the internal pressure and applying some thermodynamic arguments and approximations, the surface tension was calculated from the Kirkwood and Buff equation. Experimental pVT data of ionic liquids, in a wide temperature range, were extracted from available sources. The values of surface tension calculated by this method are in good agreement with the reported values, and the trend of their changes with temperature is also consistent with the trend of experimental data.
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