Phase behavior of sunflower oil and soybean oil in propane and sulphur hexafluoride

Phase equilibria of sunflower and soybean oils in propane and sulphur hexafluoride (SF6) have been investigated. The phase behavior of sunflower oil-propane and soybean oil-propane systems has been studied using high-pressure variable-volume cell. For both systems, the transition of the two-phase system to one-phase system was observed visually at 25 degrees C and 40 degrees C and at different system compositions generally in the range of 0.2-0.7 weight fraction of propane. Furthermore, high-pressure vapor-liquid phase equilibrium data (P-T-x-y) for the sunflower oil-SF6 and soybean oil-SF6 systems have been measured at temperatures of 25 degrees C and 40 degrees C and pressures from 10 bar to 500 bar using a static-analytic method. For the above mentioned systems with SF6 the tree phase region was observed at pressures near the phase transition of SF6 from vapor to liquid phase. Additionally, phase inversion for both investigated systems was recorded, as well. (C) 2009 Elsevier B.V. All rights reserved.