Isobaric Vapor–Liquid Equilibrium for the Binary Systems Dimethyl Disulfide + C1–C4 n-Alkanol at 40.000 and 101.325 kPa

Abstract

The vapor−liquid equilibrium (VLE) data for the binary mixtures dimethyl disulfide + methanol, dimethyl disulfide + ethanol, dimethyl disulfide + 1-propanol, and dimethyl disulfide + 1-butanol have been measured over the complete composition range at p = 40 and 101.325 kPa using a Fischer Labodest ebulliometer. All of the considered binary systems exhibit azeotropic points. The study of the effect of pressure upon the azeotropic composition shows that an increase in the number of carbons in the n-alkanol induces the composition of the azeotropic point to move toward the dimethyl disulfide-rich region. Our experimental data were correlated by the Wilson equation and checked for thermodynamic consistency. The reduced excess Gibbs function was also calculated, and the values of this property are discussed in terms of molecular interactions. Moreover, our experimental VLE data were compared with those calculated with the modified UNIFAC model with unsatisfactory results.

Vapor-Liquid Equilibrium at Several Experimental Conditions of the Binary Mixtures Methyl Lactate with n-Alkanols

“…Then, samples of liquid and condensed vapor were analyzed by densitometry using a digital densimeter (DMA 5000 model) from Anton Paar, prior to this the corresponding densitycalibration curves were obtained [13]; the uncertainty in the determination of mole fraction compositions is 0.002. The experimental equipment and operating procedures have been detailed in previous papers [14,15].…”

Volumetric Behavior and Vapor–Liquid Equilibrium of Dimethyl Disulfide + n-Alkanol Binary Mixtures

“…The vapour pressures of the pure compounds and the phase equilibria of the binary mixtures was performed using a dynamic ebulliometer (Fischer Labodest), previously described [21,22], equipped with a Cottrell pump. It is an ebulliometer with recirculation of both phases, after leaving the separation chamber the vapour phase is condensed and returned to the liquid phase.…”

“…A literature survey shows that some works related with this study have been performed. Zudkevitch et al [19] measured the isothermal VLE of dimethyl disulfide + methanol mixture at the temperatures 310.95 and 336.35 K. Uusi-Kyyny et al [20] determined the isothermal VLE of the dimethyl disulfide + ethanol system at T = 343.15 K. Recently, we have measured the isobaric vapour liquid equilibrium of these systems at p=40.000 and 101.325 kPa [21].…”