Catalytic effect of platinum on the kinetics of carbon oxidation by NO2 and O2

Opportunities for ceria-based mixed oxides versus commercial platinum-based catalysts in the soot combustion reaction. Mechanistic implications

“…This fact is in accordance with the idea that NO 2 is much more active than O 2 and can directly attack the carbon surface [28]. Actually, the activation energy measured for the direct soot-NO 2 reaction is very similar to that obtained from platinum-catalysed reaction under NOx/O 2 [21], (consistent values from TPR and isothermal conditions).…”

“…Among the several catalysts used for soot combustion, the most common are: molten salts [14][15][16][17], Pt-based oxides [18][19][20][21], ceria-based oxides [18,19,[22][23][24][25][26][27][28], and others based on transition metals (such as copper or iron) [20,24,26,[29][30][31][32][33][34]. Although those catalysts containing Pt show a very high activity in the NO oxidation to NO 2 (and thus, promoting soot combustion), some other catalysts are being developed, whose NO 2 production activities are becoming closer to those of Pt-based catalysts, but with lower costs.…”

Nitrate storage behavior of Ba/MnOx–CeO2 catalyst and its activity for soot oxidation with heat transfer limitations

“…To develop suitable catalysts capable of promoting soot oxidation by NO x is an efficient way for removal of soot at relative low temperatures. Among the catalysts investigated, novel metals such as platinum are one of the most active kinds as they can effectively catalyze oxidation of NO to NO 2 [2,3].…”

Multi-catalytic soot filtration in automotive and marine applications

“…This implies that the main soot oxidation function of platinum is indirect by converting NO to NO 2 . Jeguirim et al [11] found that Pt furthermore exerts a catalytic effect on the cooperative carbon-NO 2 -O 2 oxidation reaction by forming atomic oxygen.…”