Catalytic diesel soot elimination on Co-K/La2O3 catalysts: Reaction mechanism and the effect of NO addition

E.E. MIRÓ; F. RAVELLI; M. A. ULLA; L. M. CORNAGLIA; C. A. QUERINI

STUDIES IN SURFACE SCIENCE AND CATALYSIS

Elsevier B.V

Lugar: Amsterdam; Año: 2000 vol. 139 p. 731 - 736

0167-2991

Catalysts containing Co and/or K supported on La2O3 have been studied for diesel soot catalytic combustion. While supported Co provides redox sites for the reaction, potassium and the support itself contribute to create additional sites for soot consumption by forming carbonates intermediates. The formation of a perovskite structure after high temperature treatment leads to the lost of activity. The presence of NO in the gas phase improves the catalytic activity for soot elimination. NO is oxidized to NO2 on the catalyst surface, and NO2 is a stronger oxidizing agent than O2, therefore decreasing the temperature needed to burn the soot.