Measurement and correlation of vapor–liquid equilibria for ethanol + ethyl laurate and ethanol + ethyl myristate systems near critical temperature of ethanol

Abstract

The vapor–liquid equilibria for ethanol + ethyl laurate and ethanol + ethyl myristate systems were measured by flow method at 493–543 K and 2.11–7.09 MPa, near the critical point of ethanol ( T c = 513.9 K, p c = 6.15 MPa). The mole fractions of ethanol in vapor phase are close to unity at the pressures lower than 6.0 MPa and 493–543 K. It was found that the saturated liquid lines are almost the same for both ethanol + ethyl ester systems. These vapor–liquid equilibria were compared with those for methanol + methyl laurate and methyl myristate systems. The phase behavior was discussed in point of the kinds of alcohol and fatty acid alkyl ester. The experimental data in this work were correlated with Peng–Robinson equation of state. A conventional and Wong–Sandler mixing rules were adopted for the energy and size parameters in the equation of state. The correlated results represent the experimental data in the absolute deviations for the mole fractions of ethanol in vapor and liquid phases, 0.012 and 0.010 with the conventional mixing rule, and 0.005 and 0.036 with Wong–Sandler mixing rule.