Influence of Mn and Fe Addition on the NO x Storage–Reduction Properties and SO2 Poisoning of a Pt/Ba/Al2O3 Model Catalyst

• DOI: 10.1007/s11244-009-9345-7
• Publication Date: 2009-07-08T14:44:48Z
• Authors: P. N. Lê; E. C. Corbos; X. Courtois; F. Can; S. Royer; P. Marecot; D. Duprez
• Keywords: storage reduction; SO2 poisoning; Pt; NOx; [CHIM.CATA]Chemical Sciences/Catalysis; 02 engineering and technology; 0210 nano-technology; Ba; Fe; Mn

This work deals with the effect of Mn or Fe addition on the NO x storage–reduction properties of a Pt/Ba/Al2O3 model catalyst. NO x storage capacity, SO2 poisoning and regeneration and NO x removal efficiency under rich/lean cycling conditions are studied. Fe addition to Pt/Ba/Al2O3 leads only to a small increase of NO x storage capacity, and more interestingly, to a better sulfur removal due to the inhibition of bulk barium sulfate formation. Unfortunately, the NO x storage property cannot be fully recovered. Moreover, Fe addition results in a decrease in the NO x removal efficiency. Mn addition also improves the NO x storage capacity, but no significant influence on the sulfur elimination is observed. Mn-doped catalyst does not improve the NO x removal efficiency, but NH3 selectivity is found to drastically decrease at 400 °C, from 20 to 3%. In addition, the NO x conversion can be improved at higher H2 concentration in the rich pulse, always keeping NH3 selectivity at low level.