PERTURBATION OF MOIST CO OXIDATION BY TRACE QUANTITIES OF CH3CL

The final destruction of toxic waste in incinerators occurs in the pos t flame region. The controlling chemistry in this region may be descri bed as that of fuel-lean oxidation of CO in the presence of H2O and HC l perturbed by trace quantities of chlorinated hydrocarbons. In the pr esent study, a reaction bath with initially about 1% of CO, O-2, and H 2O in nitrogen was perturbed by CH3Cl in a turbulent flow reactor oper ating at atmospheric pressure, with temperatures between 1000 and 1150 K. The equivalence ratio ranged from 0.25 to 1.0 and the initial CH3C l ranged from 0 to 250 ppm. As little as 100 ppm of the CH3Cl were fou nd to completely inhibit the oxidation of CO. The destruction of CO an d CH3Cl was found to be most effectively enhanced first, by increasing temperature, second, by O-2 addition, and last by water addition. Spe cies concentration and temperature profiles were obtained as a functio n of reactor residence time, and were compared to predictions from a d etailed kinetic model. The observed intermediate and product species ( CO, CO2, O-2, CH2Cl, HCl, C2H4, CH4, C2H3Cl, and CH2O) were all quanti fied experimentally. While the main qualitative features of the experi ments are accurately predicted by the model, the intermediate species profiles display discrepancies. Sensitivity and reaction flux analyses indicate that, owing to the large levels of O-2 and CO, the sequence of reactions CH3Cl + Cl --> CH2Cl + HCl CH2Cl + O-2 --> CH2O + ClO ClO + CO --> Cl + CO2 provides a rapid consumption pathway of CH3Cl.