Catalyzed Particulate Filter Regeneration by Platinum Versus Noble Metal-Free Catalysts: From Principles to Real Application

BaFe1−xCuxO3 Perovskites as Soot Oxidation Catalysts for Gasoline Particulate Filters (GPF): A Preliminary Study

“…These results agree with that reported for coppersupported Ceria-zirconia catalysts for soot oxidation in GDI conditions [9]." "Copper content has a key role on the performance of the BaFe1-xCuxO3 catalyst for soot oxidation, which is in agreement with previous reports focused on diesel soot removal [13][14][15][16][17][27][28][29][30] and with that reported for copper-supported Ceria-zirconia catalysts for soot oxidation in GDSI conditions [9]." Answer to Reviewer #2 The authors synthesized composite oxides of Cu, Fe and Ba by a citrate sol-gel method, and investigated the properties and activities of the compounds obtained by their composition ratio.…”

“…These results agree with that reported for BaFe1-xCuxO3 perovskite catalysts for GPF copper-supported ceria-zirconia catalysts for soot oxidation in GDI conditions [9]. The highest soot conversion shown by the highest copper content catalysts (BFC4) seems to be related with their largest amount of -oxygen evolved, as well as with the presence of a high amount of surface copper species (as BaOx-CuOx oxide) which catalyze the soot oxidation reaction [9,[27][28][29][30]. As the performance of BFC4 is hold during a second cycle of oxidation reaction in TPR conditions (cooling down to room temperature in synthetic air after the first TPR cycle, following by addition of an identical amount of surrogated soot to carry out the second cycle), the catalytic role seems to be probed.…”

“…This value increases with the copper content from 29% for BFC0, to 44% for BFC1, 69% for BFC3 and 94% for BFC4. These results agree with that reported for BaFe1-xCuxO3 perovskite catalysts for GPF copper-supported ceria-zirconia catalysts for soot oxidation in GDI conditions [9]. The highest soot conversion shown by the highest copper content catalysts (BFC4) seems to be related with their largest amount of -oxygen evolved, as well as with the presence of a high amount of surface copper species (as BaOx-CuOx oxide) which catalyze the soot oxidation reaction [9,[27][28][29][30].…”

“…To determine the catalysts performance for soot oxidation in the highest demanding GDI exhaust conditions, Temperature Programmed Reactions (10ºC/min from room temperature till 900ºC, using a 100 ml/min flow of He to simulate the regular stoichiometric GDI operation [6]) were carried out in a TGA equipment (TGA/STDA851e/SF/1000 from Mettler Toledo) coupled to a Mass Spectrometer (Thermostar GSD301T from Pfiffer Vacuum). These experiments were run using only the perovskite catalysts (designed as O2-TPD) and soot/catalysts mixture under loose contact (1:20 ratio [9] and adding Printex U as surrogated soot). Table.1 presents the nomenclature used for the perovskite catalysts and the most relevant characterization data: BET surface area (obtained by applying the BET equation to N2 adsorption data), copper content (measured by ICP-OES) and XPS data.…”

“…As the working conditions of GPF are different to that of DPF in diesel exhaust (O2 is only available during fuel cuts) [6][7][8], catalysts able to oxidize soot with low partial pressure of oxygen, or even in the total absence of oxygen, have to be developed. However, the soot oxidation reaction in the high demanding GDI exhaust conditions has not been reported as much as Diesel soot oxidation [7][8][9].…”