High-Pressure Vapor−Liquid Equilibria in the Systems Nitrogen + Dimethyl Ether, Methanol + Dimethyl Ether, Carbon Dioxide + Dimethyl Ether + Methanol, and Nitrogen + Dimethyl Ether + Methanol

Isothermal ( P, T, x, y ) data have been measured for the binary and ternary systems nitrogen + dimethyl ether at 15, 35, and 45 °C, dimethyl ether + methanol at 80 °C, carbon dioxide + dimethyl ether + methanol at 40 and 60 °C, and nitrogen + dimethyl ether + methanol at 40 and 15 °C. The pressure range under investigation was up to 9.5 MPa. The experimental data for the binary systems were correlated with the SRK equation of state using the MHV2 mixing rule combined with the UNIFAC or UNIQUAC model for the expression of the excess Gibbs energy. The experimental data for the ternary systems have been compared with those predicted by means of the same models, and the results are discussed by comparison. The binary system of nitrogen + dimethyl ether as well as the two ternary systems have not previously been studied.