Catalytic Soot Oxidation Using Ceria, Cobalt And Copper Nanocomposites

ABSTRACTNanosized CeO2-CuO (CeCu, 2:1) and CeO2-CoO (CeCo, 2:1) were synthesized by co-precipitation from nitrate precursors using 25% ammonia solution (NH4OH) as the precipitating agent. The catalysts were calcined in air at 800°C for 4h to evaluate the thermal stability. Powder x-ray diffraction (XRD) and Dynamic Light Scattering (DLS) techniques were used for catalyst characterization. A Thermo Gravimetric/Differential Thermal Analyzer (TG/DTA) was used to determine the catalytic efficiency and soot oxidation activity. Ce-composite nanoparticles heightens the redox properties of the catalyst relative to undoped ceria. The Ce-composite samples exhibited excellent soot catalytic combustion performance by decreasing activation energy of soot oxidation.

Performance of LaBO3/HZSM-5 Catalysts for Eliminating Soot from Diesel Exhaust

The LaBO3/HZSM-5 samples were prepared by the impregnation method. The structure of catalysts was examined by XRD. The catalytic activity for the combustion of soot particulate was evaluated by a technique of the temperature-programmed reaction. In the LaBO3/HZSM-5 catalyst, the Mn as B-site ion, the catalyst was the good candidate catalyst for the soot catalytic combustion. In the LaMnO3/HZSM-5 catalyst, the catalytic activity was tunable by changing the metal components of the perovskite-type oxide at B-site, the Fe partial substitution for Mn of LaMnO3/HZSM-5 enhanced the catalytic activity, and the combustion temperature of soot particle was lower than LaMnO3/HZSM-5 sample without substitution, corresponding Tm of 401oC and the selectivity of CO2 77.0%.