Rate constants of reactions of chlorine atoms with aliphatic hydrocarbons and halogen derivatives in the liquid phase

The kinetics of liquid phase chlorination of methane in a difluorodichloromethane medium has been studied in a temperature interval of 293–150 K. The value of activation energy found for the hydrogen abstraction stage by a chlorine atom (E₁) equals 14.2 ± 2.5 kJ/mol, with the processes of chlorine atoms recombination and the cage effect being taken into account. The method of competitive reactions has been employed to assess the constants of reaction of chlorine atoms (k₁) with ethane, propane, hexane, ethylene, allyl bromide, allyl chloride, ethyl chloride, and cyclohexane in nonpolar solvents, viz. difluorodichloromethane and 1,2-dibromotetrafluoroethane. The values (k₁) obtained in the liquid phaseare two to four orders lower than those in the gas phase, while the activation energy is 2–6 kJ/mol higher.