Effect of CeO2 Doping on Structure and Catalytic Performance of Co3O4 Catalyst for Low-Temperature CO Oxidation

Abstract

The effect of CeO 2 doping on structure and catalytic performance of Co 3 O 4 catalyst was studied for lowtemperature CO oxidation. The Co 3 O 4 catalyst was prepared by a precipitation method and the CeO 2 /Co 3 O 4 catalyst was prepared by an impregnation method. Their catalytic performance had been studied with a continuous flowing microreactor. The results reveal that the CeO 2 /Co 3 O 4 catalyst exhibits much better resistance to water vapor poisoning than the Co 3 O 4 catalyst for CO oxidation. The CeO 2 /Co 3 O 4 catalyst can maintain CO complete conversion at least 8,400 min at 110°C with 0.6% water vapor in the feed gas, while the Co 3 O 4 catalyst can maintain at 100% for only 100 min. Characterizations with XRD, TEM and TPR suggest that the CeO 2 /Co 3 O 4 catalyst possesses higher dispersion degree, smaller particles and larger S BET , due to the doping of Ceria, and exists the interaction between CeO 2 and Co 3 O 4 , which may contribute to the excellent water resistance for low-temperature CO oxidation. Furthermore, the H 2 detected in the reactor outlet gas seems to indicate that the water-gas shift reaction is the more direct reason.

Flash Synthesis and CO Oxidation of Macro-/Nano-porous Co3O4–CeO2 Via Self-Sustained Decomposition of Metal–Organic Complexes

“…As compared with cobalt oxide and ceria catalysts, integrating cobalt oxides with ceria can further enhance the redox behavior for CO [10,13,14]. Thus, catalytically active Co and Ce sites in Co 3 O 4 -CeO 2 composite oxides can cooperatively enhance the catalytic activity [15][16][17][18][19][20].…”

Synergistic Coupling of the Redox Properties of Supports and Cobalt Oxide Co3O4 for the Complete Oxidation of Volatile Organic Compounds

“…In this application metal-support interaction is considered since the resulting hydrocarbon distribution from the FT reaction is particularly related to the interaction between cobalt and the support. In the CO and methane oxidation, Co 3 O 4 is associated with CeO 2 because the corresponding redox properties and catalytic activity are enhanced [17][18][19][20]. Enhanced VOCs oxidation activity was reported for cobalt oxides reducible at low temperature [4,9,[21][22][23].…”

Effect of CeO2 on the properties of the Pd/Co3O4/cordierite catalyst in the conversion of CO, NO, and hydrocarbons

“…Such resistance is important for catalysts for the neutralization of internal combustion engine exhaust gases [4]. Furthermore, palladium-promoted oxide catalysts often display higher activity toward the action of sulfur compounds than Pd/Al 2 O 3 [8].…”

“…Rare earth oxide (REO) doping may increase the activity of transition metal oxide catalysts. Considerable interest has been found in systems containing cobalt oxide (Co 3 O 4 ) with REO (CeO 2 , La 2 O 3 ), which display high activity in the oxidation of CO and hydrocarbons and the reduction of NO and may be used for the purification of automobile exhaust gases [1, [4][5][6]. The high catalytic activity of mixtures of Co 3 O 4 and CeO 2 is attributed to the formation of Co-O-Ce surface clusters during preparation [1,7].…”