Vapor–Liquid Equilibrium for Binary Mixtures of Acetates in the Direct Esterification of Fusel Oil

Abstract

In this work, isobaric vapor–liquid equilibrium data for the binary mixtures of the isobutyl acetate + isoamyl acetate and isobutyl acetate + ethyl acetate were measured using an all-glass dynamic-recirculation still equipped with a Cottrell circulation pump (Labodest VLE 602D). For the system of isobutyl acetate + isoamyl acetate the measurements were carried out at 100 and 150 kPa, while for the system isobutyl acetate + ethyl acetate they were performed at 50, 100, and 150 kPa. Vapor pressures of the pure components were also measured to verify the performance and reliability of the equilibrium still, and data were correlated with an Antoine-type expression. The equilibrium data for the pure components were in agreement with literature reports and the data for the binary solutions show a fairly ideal behavior. Binary parameters for nonrandom two liquid (NRTL) and universal quasichemical (UNIQUAC) equations were correlated with experimental data, and both models showed good agreement with experiments and can be used for process design. It was found that, in the absence of experimental data, phase equilibrium in mixtures of acetates formed in the direct esterification of the fusel oil can be confidently predicted using the UNIFAC-DMD model or even the Ideal Model.

Isobaric Vapor–Liquid Equilibrium Data for Six Binary Systems: Prop-2-en-1-ol (1)–Hexan-2-ol (2), Prop-2-en-1-ol (1)–Hexan-2-one (2), Hexan-2-one (1)–Hexan-2-ol (2), Prop-2-en-1-ol (1)–4-Methyl-pentan-2-ol (2), Prop-2-en-1-ol (1)–4-Methyl-pentan-2-one (2), and 4-Methyl-pentan-2-one (1)–4-Methyl-pentan-2-ol (2) at 101.32 kPa

“…However, in the infinite dilution zones (mole fractions lower than 0.1), the values could not be successfully adjusted for some of the systems (Figures and ). This anomaly has been reported before and is related to the dependency between the activity coefficient and the mole fractions in eq , where small changes in concentrations ( x , y ) can greatly affect the value of the coefficient when low mole fractions are used …”

“…This anomaly has been reported before and is related to the dependency between the activity coefficient and the mole fractions in eq 3, where small changes in concentrations (x, y) can greatly affect the value of the coefficient when low mole fractions are used. 35 In Figures 4 and 6, a maximum was observed in the ln γ 1 plot for the mixtures prop-2-en-1-ol−hexan-2-ol, prop-2-en-1-ol−4methyl-pentan-2-ol, and prop-2-en-1-ol−hexan-2-one. Regarding prop-2-en-1-ol−hexan-2-one, the point of inflection is located at a low mole fraction (x 1 ≈ 0.06) and the G E /RTx 1 x 2 line tends to γ 1 = 1.28.…”

Isobaric Vapor–Liquid Equilibrium for the Binary Mixture of 1-Butanol + Butyl l-Lactate at 1 and 5 kPa

“…The equilibrium points were taken at conditions of a fixed pressure and the total reflux ratio. In relation with the heating power, the condensed flux was one to two drops per second …”

“…In relation with the heating power, the condensed flux was one to two drops per second. 12 For ensuring the thermodynamic state of the system, three variables, pressure, vapor, and liquid temperatures, were considered. During the period of analysis (30 min), the standard uncertainty was used as a stability criterion.…”

“…Penã et al 7 To validate the quality of the experimental data, thermodynamic consistency tests based on the generalized Gibbs−Duhem equation have been developed over the past years. 12,13 In this work, the Van Ness and Fredenslund tests 14,15 were used as approving criteria, together with the evaluation and regression utilities implemented in Matlab and Aspen Properties 9.0.…”