Investigation of Copper-supported Ceria Nanofibers for Catalytic Oxidation of Diesel Soot

In the present research, CeO2 and CuO/CeO2 nanofibers were synthesized by electrospinning at 12 kV DC by maintaining a tip to collector distance of 10 cm. The morphology of the as-synthesized nanofibers was determined by scanning electron microscopy, and their elemental composition was verified by X-ray photoelectron spectroscopy. The activity of the prepared samples for diesel soot oxidation was determined in a bench-scale fixed bed tubular reactor, and effluent gases were analyzed by online gas chromatography. The variations of working parameters (air flow rate, catalyst-soot ratio, catalyst-soot contact type) were evaluated in a range to optimized reaction conditions for diesel soot oxidation. The catalyst with 40% CuO/CeO2 had the highest surface area, the smallest crystallite size, and the best activity for diesel soot oxidation (tight contact) at Tf = 318oC.

Cerium–zirconium mixed oxide nanostructures for diesel soot oxidation: synthesis and effect of structure

Nanorods and nanoparticles of Ce0.8Zr0.2O2 (CZ) mixed oxides were prepared by different routes and showed good activity for diesel soot oxidation.

BaFe1-xCuxO3 Perovskites as Active Phase for Diesel (DPF) and Gasoline Particle Filters (GPF)

BaFe1-xCuxO3 perovskites (x = 0, 0.1, 0.3 and 0.4) have been synthetized, characterized and tested for soot oxidation in both Diesel and Gasoline Direct Injection (GDI) exhaust conditions. The catalysts have been characterized by BET, ICP-OES, SEM-EDX, XRD, XPS, H2-TPR and O2-TPD and the results indicate the incorporation of copper in the perovskite lattice which leads to: i) the deformation of the initial hexagonal perovskite structure for the catalyst with the lowest copper content (BFC1), ii) the modification to cubic from hexagonal structure for the high copper content catalysts (BFC3 and BFC4), iii) the creation of a minority segregated phase, BaOx-CuOx, in the highest copper content catalyst (BFC4), iv) the rise in the quantity of oxygen vacancies/defects for the catalysts BFC3 and BFC4, and v) the reduction in the amount of O2 released in the course of the O2-TPD tests as the copper content increases. The BaFe1-xCuxO3 perovskites catalyze both the NO2-assisted diesel soot oxidation (500 ppm NO, 5% O2) and, to a lesser extent, the soot oxidation under fuel cuts GDI operation conditions (1% O2). BFC0 is the most active catalysts as the activity seems to be mainly related with the amount of O2 evolved during an. O2-TPD, which decreases with copper content.