Temperature Dependence of Infinite Dilution Activity Coefficients in Octanol and Octanol/Water Partition Coefficients of Some Volatile Halogenated Organic Compounds

Abstract

Infinite dilution activity coefficients and Henry's law coefficients have been measured for 11 halogenated C 1 to C 3 compounds in 1-octanol above room temperature using a gas-liquid chromatographic measurement method. Then, using our earlier data for these substances in water and a correlation relating the limiting activity coefficients of a substance in pure water and in pure 1-octanol to their octanol/water partition coefficients, these latter quantities have been computed. One conclusion from these measurements is that the limiting activity coefficients in octanol and the octanol/water partition coefficients of the halogenated compounds studied are only weakly dependent on temperature over the range from 25 to 50°C. Also, from these and our earlier data, we have estimated the infinite dilution partial molar excess enthalpies and excess entropies of these compounds in both 1-octanol and water.