CENTRO DE INVESTIGACION Y DESARROLLO EN CIENCIAS APLICADAS "DR. JORGE J. RONCO"
Unidad Ejecutora - UE
Zirconia-Supported Cu-KNO3 Catalyst: Characterization and Catalytic Behavior
ILEANA DANIELA LICK, ALFREDO L. CARRASCUL, MARTA I PONZI, ESTHER N. PONZI
INDUSTRIAL & ENGINEERING CHEMICAL RESEARCH
Año: 2008 vol. 47 p. 3834 - 3834
The catalytic combustion of diesel soot was studied in the presence of catalysts: CuZrO2, KNO3ZrO2, and CuKNO3ZrO2. The catalysts were prepared by impregnation of ZrO2 · nH2O into an aqueous solution of Cu(NO3)2, KNO3, or both salts simultaneously. The catalysts were characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC), and temperature-programmed reduction (TPR). Cu(n)KNO3ZrO2 catalysts present high activity, and the value of the combustion temperature decreases 200 °C with respect to the temperature of the process without catalyzing, with Tmax values between 370 and 380 °C. The activity isassociated with KNO3 presence, and the role of KNO3 can be attributed to (i) an increase of contact between soot and the surface of the catalyst and (ii) a redox reaction in which the nitrate is reduced to nitrite by reaction with carbon and again reoxidized to nitrate. The copper contribution is associated with the reaction selectivity toward CO2 formation.