Total oxidation of some chlorinated hydrocarbons with commercial chromia based catalysts

Catalytic total oxidation of some chlorinated hydrocarbons (Cl-VOCs) is studied here with four chromia-based commercial catalysts. Catalysts used are: ARI Econ Abator from Wheelabrator, PRO*CLEAN*110 and PRO*HHC*Base from Sud-Chemie AG and R-3-20 from BASF AG. Two different reactors, at two different scales, have been used: a small glass-made reactor for pure and targeted Cl-VOCs, and a metallic reactor at pilot scale located in a slip flow after a fluidized bed incinerator of waste containing PVC. Pure Cl-VOCs used have been ethyl chloride, dichloromethane, trichloroethane and chlorobenzene. Conversions and product distributions are given here at different temperatures, space-velocities and concentrations at inlet. These results, once compared with the ones simultaneously got for other types of catalysts (Pt and V2O5 based) will serve to rank the commercial catalysts used here according to their activity and selectivity The chromia-based catalysts tested here have proved to be quite active but they also lose some chromium from the catalyst, by attack of the nascent Cl-2, having thus a short life when the Cl-content in the flue gas is relatively high. (C) 1999 Elsevier Science B.V. All rights reserved.