Measurement and modeling of high-pressure (vapour + liquid) equilibria of (CO2 + alcohol) binary systems

An apparatus based on a static-analytic method assembled in this work was utilized to perform high pressure (vapour + liquid) equilibria measurements with uncertainties estimated at <5%. Complementary isothermal (vapour + liquid) equilibria results are reported for the (CO₂ + 1-propanol), (CO₂ + 2-methyl-1-propanol), (CO₂ + 3-methyl-1-butanol), and (CO₂ + 1-pentanol) binary systems at temperatures of (313, 323, and 333) K, and at pressure range of (2 to 12) MPa. For all the (CO₂ + alcohol) systems, it was visually monitored to insure that there was no liquid immiscibility at the temperatures and pressures studied. The experimental results were correlated with the Peng–Robinson equation of state using the quadratic mixing rules of van der Waals with two adjustable parameters. The calculated (vapour + liquid) equilibria compositions were found to be in good agreement with the experimental values with deviations for the mol fractions <0.12 and <0.05 for the liquid and vapour phase, respectively.