A theoretical kinetic study of the methane’s hydrogen abstraction by chlorine at a large temperature range
摘要
The kinetics and mechanism of methane CH4 reaction with chlorine Cl atoms have been previously investigated using quantum theoretical calculations. In this study, we have investigated the hydrogen abstraction reaction by DFT using the CBS-QB3 method. Moreover, we have employed the Rice-Ramsperger-Kassel-Marcus theory to compute the rate constants of the reaction at a pressure of 1 atm and in the 295–1104 K temperature range. This study offers for the first time the theoretical mechanism and kinetic determination of the CH4 + Cl reaction, over a wide temperature interval, as well as its importance in the halogenation reaction. The obtained rate constant was found to be k(T) = 7.29 × 10‒19 × exp(‒287.65/T) cm3.molecule‒1.s‒1 and is in reasonable accord with that observed for CxHyCl, both theoretically and experimentally.