Catalytic Combustion of Soot over the Highly Active (La_0.9K_0.1CoO₃)_x/nmCeO₂ Catalysts

Abstract

The highly active (La 0.9 K 0.1 CoO 3 ) x /nmCeO 2 catalysts consisting of comparably sized La 0.9 K 0.1 CoO 3 active component and CeO 2 support nanoparticle were studied on the catalytic combustion of soot by temperatureprogrammed oxidation (TPO) technique. The properties of oxygen species and the redox performances of catalysts were investigated by the method of O 2 -TPD and H 2 -TPR. During TPO process, all supported oxide catalysts showed lower T m than the corresponding nanometer CeO 2 support or pure La 0.9 K 0.1 CoO 3 perovskite. The best catalytic activity was obtained over (La 0.9 K 0.1 CoO 3 ) 20 /nmCeO 2 catalyst (T m ) 354°C), and its catalytic activity for the combustion of soot is as good as supported Pt catalysts. During the catalytic combustion of soot, the surface R oxygen species should play an important role. The formation of surface oxygen-containing complexes (SOC) may be one of the key intermediate species according to the results of in situ DRIFT, and NO 2 released by surface nitrate species remarkably promote the soot oxidation.

Synergetic effects of plasma and metal oxide catalysts on diesel soot oxidation

“…On the other hand, the loaded DPF can cause a backpressure potentially decreasing the engine efficiency. Hence, a regeneration step at above 600 • C is mandatory to thermally remove the soot deposits from the filter, while the diesel exhaust gas is typically at 180-400 • C [4,5].…”

Highly Active Catalysts of Gold Nanoparticles Supported on Three‐Dimensionally Ordered Macroporous LaFeO3 for Soot Oxidation

“…Efficient exhaust gas treatment systems are dependent on the catalytic performance of oxidation catalysts, especially catalysts with very low ignition temperature (T ig ). Some nonnoble metal oxide catalysts such as transition-metal oxides, [2] alkaline metal oxides, [3] perovskite-like type oxides, [4] and ceria-based oxides [5] have exhibited good catalytic performance for diesel soot combustion. However, it is very hard to get the T ig lower than 250 8C (as seen by Table S1 in the Supporting Information).…”

Perovskite-Based Lean-Burn NO x Trap Catalysts Without Using Platinum Group Metals: K/LaCoO3/Ce1−x Zr x O2

“…Since the amount of perovskite LaCoO 3 in the supported catalysts is much larger than that of Pt, more obvious decrease in specific surface area for L/K/CZ x is natural. Even so, the specific surface area of L/K/CZ x is still much larger than that for bulk perovskites and other supported ones [5][6][7][8][9][10].…”

“…So, it is necessary to explore new kinds of LNT catalysts without using noble metals to lower the catalyst cost. It is well known that perovskites have good redox property and high thermal stability, so, they are often used for CO, VOC and soot oxidation [5][6][7][8], and NO reduction by CO or C 3 H 6 [9][10][11]. Compared with supported Pt catalysts, perovskites sometimes display comparable or higher activity [12].…”