Kinetics of the gas phase fluorination of hydrogen and alkanes

Abstract

The rates of the hydrogen abstraction reactions of fluorine atoms with hydrogen, four alkanes and methyl chloride were measured in the gas phase using a competitive technique. The compounds were arranged in the following series in which adjacent pairs were competed for fluorine: (i) H₂, CH₄, C₂H₆, H₂(ii)CH₃Cl, C₂H₆, C₃H₈, CH₃Cl. New values of the activation energy for CH₄ and C₂H₆ of 1850±230 and 480±20 cal mol^–1 respectively have been determined which are free from self-heating errors and are internally consistent when calculated from different competitive routes. A value of 2470±270 cal mol^–1 for H₂ has been similarly obtained, which differs from previously reported values based on erroneous values for methane and ethane.