abstracts - Институт катализа им. Г.К. Борескова

OP-I-15SIMULTANEOUS PROPENE AND CARBON BLACK COMBUSTION OVERRu/CeO 2 CATALYSTS. DEACTIVATION STUDY OF THE CATALYSTSAouad S., Saab E., Abi-Aad E., Aboukaïs A.Laboratoire de Catalyse et Environnement E.A. 2598, Université du Littoral - Côte d’Opale,MREI-1, 145, av. M. Schumann, 59140 Dunkerque, FranceE-mail: aboukais@univ-littoral.frReducing the particulate matter (PM) and VOCs emissions simultaneously has been amajor challenge for car manufacturers and researchers. Emission control strategies includechanges and improvements in the fuel used, engine modifications or exhaust after treatmentsystems. These latter provide satisfactory results for compliance with the emission regulationswhere the engine modifications or fuel improvements are not sufficient. Using oxidationcatalysts in order to oxidize diesel soot is one of the promising after-treatment systems. Thesecatalysts also provide significant reductions in the CO and HC emissions. They were reportedto be active in PM reduction especially when low sulfur fuel is used.Many kinds of catalysts have been studied for soot combustion applications, includingsingle and mixed transition metal oxides, perovskite- and spinel-type oxides, and low meltingpoint compounds. Most of them were tested based on a tight soot/catalyst contact which isusually obtained by mechanically mixing the soot and catalysts. However, Neeft et al. foundthat the practical physical contact between soot and catalyst in a filter is much closer to a“loose” contact condition [1].Ruthenium oxide catalysts have been demonstrated to be active in acetic acid [2] andpropene oxidation [3] reactions. The pronounced activity of ruthenium oxide catalysts seemsto stem form the reducibility of the oxide itself. In the presence of another reducible oxidesuch as CeO 2 , the oxygen needed for the oxidation reaction was reported to be provided bythe second oxide.In this study, the relationship between the oxidation state of Ru on CeO 2 support andcatalytic activity in the total oxidation of propene and carbon black is simultaneouslyinvestigated for catalysts prepared by different impregnation methods. It is demonstrated thatthe addition of ruthenium to ceria (CeO 2 ) significantly improves the reactivity: thetemperature of carbon black oxidation decreases by 100 °C (catalysts reactivity in the carbonblack oxidation was evaluated under “loose contact” conditions). It is also shown that theaddition of Ru is very beneficial for the total oxidation of propene. The reactivity for thesimultaneous combustion of carbon black and propene was also investigated.106