Reaction Mechanisms of Lean-Burn Hydrocarbon SCR over Zeolite Catalysts

The characterization and activity of F-doped vanadia/titania for the selective catalytic reduction of NO with NH3 at low temperatures

“…Wang et al [39] have proposed that the NO y groups are formed from NO and an adsorbed superoxide ion. This important role of superoxide ions in the low-temperature SCR process has been confirmed by other studies [40,41]. Therefore, we also investigated the superoxide ion content on the catalyst surface.…”

Lean NO x Reduction with Various Bio-Diesels as Reducing Agents

“…All purely hydrocarbon based fuels (paraffinic and olefinic) with a longer carbon chain than octane i.e., MK1, GTL, and NExBTL give a lower NO x reduction than octane. This is in accordance with previous studies on alkanes indicating that there is a maximum in NO x conversion as a function of carbon number, of around 6 [10][11][12]. B15 shows the highest conversion at 350°C closely followed by Agrodiesel 15.…”

Structural Characterization of Automotive Catalysts

“…A possibility discussed is to reduce the NO x by other exhaust components, like CO or HC, but this reduction is kinetically unfavoured in contrast to the oxidation with excessive O 2 in the gas phase, although a selective reduction of NO x by stoichiometric HC over Cu loaded zeolites seems to be a promising way. [5,19] Another concept tries to store NO x under lean conditions, and to release and reduce the trapped NO x periodically by switching into a stoichiometric or rich mode. [20] But up to now, no convincing technique has been found to eliminate nitrogen oxides from the diesel exhaust.…”