The thermal reaction of trans-1,2-dichloroethylene (DCEE) in methane and oxygen mixtures in Ar bath gas has been studied in 10.5 mm I.D. tubular flow quartz reactors at I atmosphere pressure, isothermal temperature between 575°C and 1000°C, and times of 0.3 to 2.0 seconds.

The thermal reaction of trans-1,2-dichloroethylene in the gas phase proceeds via unimolecular HCI elimination under the reaction condition of the present experiments. The chain branching C-Cl bond fission reaction is expected to become important at the higher temperature, competing With the HCI elimination.

The decay trans- 1,2- dichloroethylene, intermediates and final product distributions varied in the absence and presence of added O₂ and/or CH₄. Increase in O₂ concentration was observed to accelerate reagent loss in the DCEE/CH₄/O₂ system, especially the fuel lean and stoichiometric systems relative to the DCEE/CH₄ system. Major products were C₂H₂, HCCCl, CH₂CHCl, CH₂CCl₂, C₆H₆, CO, CO₂, and HCl in the DCEE/CH₄/O₂ over a wide temperature range. Minor products were C₂H₄, CH₂Cl, CH₂O₂, C₂O₂, CH₃CCl₃, C₆H₅Cl, C₆H₅CH₃.

The extensive experimental data set will be utilized for construction and validation of a mechanism consisting of elementary reactions based on thermochemical principles, Transition State Theory and Quantum Rice-Ramsperger-Kassel (QRRK) analysis.