Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

ABSTRACT

Liquid-liquid equilibria (LLE) data are presented for three ternary systems: 2,2-dimethyl-1,3-dioxolane- 4-methanol (DMDM) + n-heptane + ethanol, and DMDM + n-heptane (or toluene) + water. The most of the measurements were performed at 293.15K and atmospheric pressure, some data obtained relate to 273.15K. The phase diagrams for the ternary system containing n-heptane and water show the extended heterogeneous area between the water hydrocarbon side of the concentration triangle and the n-heptane-DMDM side. Much smaller regions of immiscibility with the critical points are observed for the ternary mixtures DMDM + toluene + water and DMDM + n-heptane + ethanol. The experimental LLE data were correlated applying the NRTL model. The UNIFAC interaction parameters for CH2O groups of DMDM were estimated on the base of LLE in the DMDM + n-heptane + ethanol system. The UNIFAC model was applied to predict the LLE diagrams for ternary DMDM + n-heptane (or toluene) + water solutions. Both NRTL and UNIFAC models with the estimated parameters have provided satisfactory results.