KINETICS OF SOOT-O-2, SOOT-NO AND SOOT-O-2-NO REACTIONS OVER SPINEL-TYPE CUFE2O4 CATALYST

Kinetics of soot-O-2, soot-NO and soot-O-2-NO reactions over CuFe2O4 w ere investigated by using temperature programmed reaction (TPR) techni que in which a soot-catalyst mixture was loaded in a reactor and expos ed to a fluent stream containing gaseous reactant(s) under a constant heating rate. Within the temperature range where a substantial amount of the charged soot remained and the reaction can be regarded to be th e zero order in the amount of soot, the kinetic analysis of non-steady TPR results was possible. The half-order kinetics in the partial pres sure of O-2 (P-O2) was obtained for the soot-O-2 reaction. The soot-NO reaction was complicated in the temperature dependence of CO2 and N-2 formation as well as in the reaction order with respect to P-NO; the reaction order was first at lower temperatures and increased with incr easing temperature. In the soot-O-2-NO reaction, i.e. the so-called si multaneous soot-NOx removal, the rate of CO2 formation and those of bo th N-2 and N2O formation depended on partial pressures as (PNOPO20.6)- P-0.6 and (PNOPO20.4)-P-1.0 respectively. Based on the kinetic results , possible reaction mechanisms were discussed.