Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

ABSTRACT

The critical temperatures (Tc) and critical pressures (pc) of five binary mixtures (DEC + hexane, DEC + heptane, DEC + octane, DEC + cyclohexane, DEC + ethanol) and a ternary mixture (DEC + ethanol + heptane) were determined over the whole range of concentration using an accurate experimental apparatus based on flow method. The combined standard uncertainty of temperature is 0.2 K while that of pressure is 5.2 kPa. The critical temperatures of DEC + octane and DEC + cyclohexane mixtures present a non-ideal behavior. The maximum average absolute deviations of Redlich-Kister equations for Tc and pc of five binary mixtures are 0.08% and 0.41%, respectively. Cibulka's equations and Singh-Sharma's equations were used to correlate the critical parameters of ternary mixture. The critical surfaces of ternary mixture were plot using Cibulka's equations.