This study aims to make detailed measurements of the solubility data for perfluoroalkane + n-alkane systems. Using a laser-scattering technique developed in our laboratory, we determined the liquid-liquid equilibria (LLE) for three binary mixtures: perfluorohexane + n-hexane, perfluorohexane + n-octane, and perfluorooctane + n-octane. The experimental LLE data were represented by the NRTL equation. In addition, the activity coefficients obtained from the experimental LLE data were compared with those obtained from the vapor-liquid equilibrium (VLE) data. (C) 2010 Elsevier B.V. All rights reserved.