Measurement and modeling of surface tensions of asymmetric systems: heptane, eicosane, docosane, tetracosane and their mixtures

To extend the surface tension database for heavy or asymmetric n-alkane mixtures, measurements were performed using the Wilhelmy plate method. Measured systems included the binary mixtures heptane+eicosane, heptane+docosane and heptane+tetracosane and the ternary mixture heptane+eicosane+tetracosane at temperatures from 313.15 K (or above the melting point of the mixture) up to 343.15 K. All the measurements were performed at atmospheric pressure. these data, along with data previously measured by us and collected from the literature, a recently proposed corresponding states model was assessed. It is shown that using a new generalized combining rule for the critical temperature, the data can be described with deviations of about 1% that is within the experimental uncertainty of the measurements.