Phase behavior of CO2 + polyethylene glycol + ethanol at pressures up to 20 MPa

Phase behavior for carbon dioxide (CO2) + poly(ethylene glycol) (PEG1000, PEG6000, PEG20000) + ethanol mixtures were measured at pressures up to 20 MPa. To determine the phase boundary, we observed the cloud point using a variable volume view cell. The one-phase region increased with increasing pressure and decreasing molecular weight of PEG. The Sanchez–Lacombe equation of state was used to correlate the phase behavior of these systems.