Abstract: Vapor-liquid equilibrium data of the supercritical carbon dioxide+diethyl carbonate system were measured isothermally at 333, 353, 373 and 393 K in the pressure range of 3-15 MPa. The measurements were carried out in a cylindrical autoclave with a movable piston and an observed window. It is shown that the solubilities of supercritical CO₂ in DEC increase drastically with the increase of pressure at the given temperature, but the content of DEC in gas phase increase faintly. The critical values p_c,T_c,x_c and V_c of the binary system were predicted.

Key words: High-pressure phase equilibrium, Diethyl carbonate, Supercritical CO₂, Critical properties