Journal article
Combination of Ag/Al2O3 and Fe-BEA for High-Activity Catalyst System for H2-Assisted NH3-SCR of NO x for Light-Duty Diesel Car Applications
Low-temperature active Ag/Al2O3 and high-temperature active Fe-BEA zeolite were combined and tested for H2-assisted NH3-selective catalytic reduction (SCR) of NO x . The catalysts were either washcoated onto separate monoliths that were placed up- or downstream of each other (dual-brick layout) or washcoated on top of each other in a sandwiched layout (dual-layer).
Our results showed that it is highly preferred to have Ag/Al2O3 as the upstream or outer layer catalyst. Fe-BEA showed a high NH3 oxidation giving an NH3 deficit over the Ag/Al2O3. Ag/Al2O3 formed NO2 which enhanced the activity over Fe-BEA through the “fast”-SCR reaction when Fe-BEA was placed downstream or as inner layer.
When no H2, which is needed for the SCR reaction over Ag/Al2O3, was added, the dual-layer layout was preferred. The shorter diffusion distance between the layers is a probable explanation.
| Language: | English |
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| Publisher: | Springer US |
| Year: | 2013 |
| Pages: | 14-18 |
| ISSN: | 15729028 and 10225528 |
| Types: | Journal article |
| DOI: | 10.1007/s11244-013-9921-8 |
