High-pressure vapor-liquid equilibrium for dimethyl ether + 2-propanol and dimethyl ether + 2-propanol + water

We report vapor-liquid equilibrium data for the system dimethyl ether (DME) + 2-propanol at 323.45, 348.45, and 373.45 K and for the system dimethyl ether + 2-propanol + water at 323.25, 348.05, and 373.15 K. The experimental data are correlated using the Peng-Robinson equation of state and the Elliott-Suresh-Donohue equation of state. We explore the properties of dimethyl ether in the ternary system as a near-critical or supercritical solvent or cosolvent. The data for the dimethyl ether solutions are compared to literature data for ternary systems containing propylene or propane + 2-propanol + water. Dimethyl ether exhibits relatively higher solubility in the aqueous phase, leading to enhanced volatility of water at relatively low pressures compared to the case for propane. On the other hand, dimethyl ether also becomes completely soluble in the aqueous solution at relatively low pressures, precluding two-phase mass transfer under certain conditions.