High-pressure vapor–liquid equilibria of methanol + propylene: Experimental and modeling with SAFT

The high-pressure vapor–liquid equilibria of methanol + propylene was measured experimentally within a temperature and pressure range of 293–373 K and 0.17–3.7 MPa, respectively, using a synthetic method. The system showed a highly non-ideal behavior with positive deviation from Raoultʹs law. The phase behavior was also modeled by the statistical associating fluid theory (SAFT) and the Soave–Redlich–Kwong (SRK) equations of state. The statistical associating fluid theory correlated the phase behavior of the binary system much better than the Soave–Redlich–Kwong model, especially at higher pressures. For example, the average absolute deviation percent (AAD%) at T = 370 K was 1.11% for the SAFT model with k12 = 0.02088 and 6.75% for the SRK model with k12 = 0.08035.