High pressure vapor-liquid equilibria for supercritical trifluoromethane and C5-hydrocarbons systems

In order to investigate the effect of the polarity of a supercritical fluid on the solubility of C5-hydrocarbons, isothermal high pressure vapor-liquid equilibria for three binary systems(CHF3-n-pentane, CHF3-isopentane and CHF3-isoprene) and a ternary system (CHF3-isoprene-n-pentane) were measured at 310K and 343K by using a static type of apparatus. On the basis of the data measured in this work and reported in the literature, it was found that (1) the Peng-Robinson equation of state satisfactorily correlated the binary systems except near the critical region, but deviations for the ternary system were larger than those for the binary systems; (2) the intermolecular force between a polar supercritical fluid such as CHF3 and a slightly polar solute such as isoprene was not strong enough to extract the solute selectively from the mixture of hydrocarbons having the same carbon number; and (3) supercritical fluids of high critical temperatures and having a chemical structure similar to that of solute exhibited greater solvent power.