Effect of Pt and Ba content on NO x Storage and Reduction Over Pt/Ba/Al2O3

Abstract

Effects of Pt and Ba content of Pt/Ba/Al 2 O 3 on NO x storage reduction (NSR) catalyst were investigated by means of kinetic analysis of surface nitrates using in situ FT/IR. Turnover frequencies of both storage and reduction of nitrate were significantly enhanced at higher Ba content, while those were higher at lower Pt content below 0.2 wt%.

Influence of Pt Loading in Aged NOx Storage and Reduction Catalysts

“…As the precious metal component/s is/are the most costly aspect of the device, a clear understanding of loading/dispersion effects would appear essential. However, a review by Roy and Baiker highlighted the fact that detailed studies relating Pt dispersion and NSR activity have not been performed although there are now a few very recent contributions which deal with this issue. − A further issue to note is that by far the majority of laboratory scale studies involving Pt-based NSR catalyst involve freshly prepared samples. However, it is well-known that rapid changes to dispersion occur during early stages of operation of such catalysts and hence laboratory findings based on comparisons of fresh catalysts may be difficult to extrapolate to more applied investigations.…”