Influence of chlorine on methane oxidation

Experiments on CH4/Cl2/O2/N2 oxidation were conducted in an atmospheric pressure flow reactor to understand the influence ofchlorine on hydrocarbon oxidation in hazardous waste incineration. The reaction temperature varied from 973 to 1273 K and thechlorine to hydrogen mole ratio (Cl/H) of the inlet mixture varied from 0 to 0.44. The species produced in the reaction were measuredonline with Fourier transform infrared spectroscopy (FT-IR). It was found that the destruction and removal e ciency of CH4 increasedwith Cl/H mole ratio. Increasing Cl/H favored COCl2 and CO formation and inhibited the CO oxidation process. As Cl/H approached0.44, the concentrations of CH2Cl2 and CH3Cl first increased, and then declined. Reaction temperature greatly a ected the reactionsystem. Increasing temperatures raised the destruction removal e ciency of CH4 and decreased the concentrations of CH3Cl andCH2Cl2. With a certain ratio of Cl/H, the concentrations of CO and COCl2 first increased and then declined. The CO and COCl2concentration peak was observed around 1100 K and 1023 K, respectively. When the reaction temperature exceeded 1273 K, carbon inCH4 was mostly converted to CO2. It could be concluded that the presence of chlorine enhanced the destruction of CH4, but resulted inthe more toxic incomplete combustion products emission such as COCl2 when the reaction temperature was not high enough.