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In this work the parameters of a PC-SAFT model combined with the group contribution of Tamouza et al. [Fluid Phase Equilib. 228–229 (2005) 409–419. http://dx.doi.org/10.1016/j.fluid.2004.10.003] were estimated using not only pure component experimental data, but also mixture vapor–liquid equilibrium (VLE) and infinite–dilution activity coefficient (IDAC) data. With the resulting parameters, the percent average absolute deviation values for vapor pressure and molar liquid volume were under 2.6% for n-alkanes and were under 7.4% for vapor pressure and 2% for molar liquid volume for 1-alkanols. For the studied mixtures, the average absolute relative deviation for bubble pressures was under 5.2%, considering 1239 experimental VLE data points in the temperature range from 273 to 422 K. For IDAC, the predictions were very similar to those obtained by other similar models. These results reveal that the proposed group contribution PC-SAFT model can be used to predict vapor–liquid equilibrium with a satisfactory accuracy for 1-alkanols and n-alkanes binary systems with no binary interaction parameter.

Cubic equations of state combined with excess Gibbs energy predictive models (like UNIFAC) and equations of state based on applied statistical mechanics are among the main alternatives for phase equilibria prediction involving polar substances in wide temperature and pressure ranges. In this work, the predictive performances of the PC-SAFT with association contribution and Peng-Robinson (PR) combined with UNIFAC (Do) through mixing rules are compared. Binary and multi-component systems involving polar and non-polar substances were analyzed. Results were also compared to experimental data available in the literature. Results show a similar predictive performance for PC-SAFT with association and cubic equations combined with UNIFAC (Do) through mixing rules. Although PC-SAFT with association requires less parameters, it is more complex and requires more computation time.