During the exploration of the possible use of an extraction process for the separation of gaseous cascade impurities from uranium hexafluoride, a number of short exploratory studies were carried out. These included (1) experimental determination of the vapor pressure and liquid density of perfluorodibutylcylicether, (2) calculation of the liquid vapor-equilibria of the systes perfluoro-n-pentane-uranium hexafluoride and 1,2-dichlorohexafluoropropane-uranium hexafluoride, and (3) derivation of equations for the estimation of activity coefficients in ternary systems from the properties of the pure components. The results of these studies are summarized in this report.