CATALYTIC STEAM REFORMING OF CHLOROCARBONS - METHYL-CHLORIDE

This paper reports a novel catalytic process for the destruction of ch lorinated hydrocarbons. Based on CH4-steam reforming reactions, the ap proach gives high levels of conversion (5-nines possible) at high spac e velocities (2-3 x 10(5) h(-1)) and temperatures (650-750 degrees C). Products comprise CO, CO2, H-2 and HCl and no others were identified. Rapid deactivation by parallel thermal pyrolysis reactions occurs if high conversion is not maintained. The presence of Cl species poisons CH4-steam reforming and water gas shift activities, but the effect is only temporary and disappears when the Cl compounds are removed from t he feed. Kinetic studies on methyl chloride have been carried out and show a Langmuir-Hinshelwood type behavior, from which a proposed mecha nism involving dual-site surface dissociation is suggested. Comparison s with other common chlorocarbons show similarities, with the exceptio n that 1,1,1-trichloroethane is very sensitive to thermal pyrolysis an d gives faster deactivation.