Semi-analytical nanoscale-extended surface tension correlation

Surface tensions (STs) are of critical importance to numerous natural phenomena and practical applications while most existing ST correlations are in the empirical formulations and limited to the bulk phase. In this study, a new semi-analytical correlation based on the perturbation theory from the statistical thermodynamics is initially developed to calculate the STs of the various components in bulk and nanoconfined pores. The newly developed ST correlation is validated to be accurate and generalized in bulk and nanoconfined pores in comparison with the experimentally measured results at a wide range of temperatures. Furthermore, three important patterns with respect to the STs are determined: first, the STs are found to be reduced with the temperature increase but increase when the components become heavier in both bulk and nanoconfined pores; second, the STs of the mixtures tend to be more sensitive to the feed ratios at higher temperatures; last but not least, the nanoscale STs of the pure components are slightly lower than the bulk results at the same conditions.