Abstract

This experimental work describes the thermodynamically consistent determinations of the phase equilibria at the isobaric conditions of 50, 75, and 94 kPa covering the temperature range from 353 to 402 K; the isobaric-isothermal surface tensions and the isobaric-isothermal liquid dynamic viscosities at 101.3 kPa and 298.15 K and over the entire mole fraction range for the propan-1-ol + dibutyl ether binary mixture. The experimental measurements of phase equilibria are measured in an all-glass dynamic vapor-liquid cell. The isobaric-isothermal surface tensions are measured in a maximum differential bubble pressure tensiometer, whereas the isobaric-isothermal liquid viscosities are measured in a Stabinger viscometer. Based on the experimental results of the vapor-liquid equilibria, this binary system exhibits a positive deviation from the ideal behavior, showing an estimated minimum temperature azeotrope at 50 and 75 kPa. The azeotropic concentration increases with pressure and/or temperature and ends at the pure propan-1-ol. The surface tension of the explored binary mixture shows a negative departure from the linear behavior of the surface tension, and an aneotropic point is detected near pure dibutyl ether; after this azeotropicpoint, the surface tension increases as the propan-1-ol liquid mole fraction increases. The liquid dynamic viscosity increases as the propan-1-ol liquid mole fraction increases. The reported results for both the surface tension and liquid dynamic viscosity agree with previous works. Wisniak and Fredenslund's thermodynamic consistency evaluation confirms the reliability of the reported vapor-liquid equilibrium data, which are also correlated with four activity coefficient models, namely, the three-suffix Margules model, the Wilson model, the nonrandom two-liquid (NRTL) model, and the universal quasichemical (UNIQUAC) group contribution model. On the bases of these results, the three-suffix Margules activity coefficient model provides the lowest deviation. The experimental determinations of the isobaric-isothermal surface tension and the isobaric-isothermal liquid dynamic viscosity of the binary mixture are correlated with the mole fraction by using a three-order Redlich-Kister-type polynomial showing a low deviation.