Investigation of the Low-Pressure Phase Behavior and SAFT Modeling of 1-Alcohol and n-Alkane Binary Systems

The low-pressure phase behavior of 1-alcohol + n-alkane systems is investigated by considering trends in the experimental data and the ability of SAFT models to predict the data. Data for four new isobaric binary 1-alcohol + n-alkane systems at 40 kPa are presented in this study, including 1-heptanol + n-octane, 1-octanol + n-nonane, 1-nonanol + n-decane, and 1-decanol + n-undecane. These systems were not azeotropic, although positive deviations from ideality were observed. The C_nOH + C_n+1 data were compared to the previously measured data for the C_nOH + C_n+2, C_nOH + C_n+3, and C_nOH + C_n+4 systems, and trends and observations were elucidated. It was concluded that the azeotropic composition could be predicted for other systems not considered in these studies based on the available data. Finally, the modeling of the available n-alkane and 1-alcohol data was considered using the PC-SAFT and SAFT-VR-Mie models, and SAFT-VR-Mie consistently outperformed PC-SAFT.