Phase equilibrium data of the system CO2 + glycerol + methanol at high pressures

In this work, phase equilibrium data of the ternary system CO2(1) + glycerol(2) + methanol(3) at high pressures are presented. The static synthetic method using a variable-volume view cell was employed to obtain the phase envelope in the temperature range of 303.15–343.15 K and at pressures up to 22 MPa. For the pressure transition measurements a given amount of carbon dioxide was injected into a methanol:glycerol mixture with a known molar ratio. Three different methanol to glycerol molar ratios were investigated (1:30, 1:20 and 1:12). The mole fraction of carbon dioxide was varied according to the system as follows: 0.3373–0.9741 for the glycerol to methanol molar ratio of 1:30, 0.2524–0.9949 for the molar ratio of 1:20, 0.2625–0.9940 for the molar ratio of 1:12. A complex phase behavior including vapor–liquid (VL), liquid–liquid (LL) and vapor–liquid–liquid (VLL) transitions were observed for these systems.

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► We measured phase behavior for the system involving CO2 + glycerol + methanol.
► The saturation pressures were obtained using a variable-volume view cell.
► VLE, LLE and VLLE were observed.