Phase equilibrium for (camphor + CO2), (camphor plus propane), and (camphor + CO2 + propane)

Phase equilibrium data for {camphor ( 1) + CO2 ( 2)}, {camphor ( 1) + propane ( 3)}, and {camphor ( 1) + CO2 ( 2) + propane ( 3)} were measured using a high-pressure variable-volume view cell and the synthetic static method; experiments were performed at temperatures of ( 304, 314, 324, 334, 344, 354, 364, 374, and 384) K. The phase transitions have been visually identified as bubble and dew points. The temperature and pressure uncertainties were 0.5 K and 0.07 MPa. The experimental data were described satisfactorily by the Peng-Robinson equation of state with vdW2 mixing rule. The binary interaction parameters (k(12) and l(12)) were estimated by heuristic optimization using the simulated annealing (SA) method. Propane considerably affected the phase behavior of camphor + CO2 when used as a second solvent, resulting in pressures for the LV phase transition intermediate to the phase transition pressure of the binary systems investigated.