Vapor–liquid phase equilibrium behavior of mixtures containing supercritical carbon dioxide near critical region

A new visual and volume-variable high-pressure phase equilibrium analyzer (PEA) was installed for determining the vapor–liquid phase boundaries over a wide pressure range, including near critical region, by a synthetic method. This apparatus was tested with the measurement of CO2 + 1-octanol. The PEA was also utilized to measure the isothermal vapor–liquid phase boundaries of CO2 + dimethyl sulfoxide, CO2 + propylene glycol monomethyl ether acetate, and CO2 + quinoline at temperatures from 308.15 to 358.15 K and pressures up to 28 MPa or near critical pressures. These phase boundary data were correlated with the Soave, the Peng–Robinson and the Patel–Teja equations of state, respectively.