| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 47603 | Applied Catalysis B: Environmental | 2009 | 4 Pages |
Abstract
The SOx storage and release kinetics on CeO2 have been studied by lean SOx adsorption and temperature programmed desorption for different pairwise configurations of individual monolith samples, i.e., Pt/CeO2Â +Â SiO2, Pt/SiO2Â +Â CeO2, CeO2Â +Â Pt/SiO2 and CeO2Â +Â SiO2. In the case of sole ceria, SOx adsorption proceeds both via SO2 and SO3 adsorption although the latter channel is kinetically favored. Hence, the rate of SO2 oxidation is crucial for the overall SOx storage kinetics. It is also found that physical contact between Pt and ceria is important for the storage process. This is attributed to efficient transport routes for SOx (surface diffusion and spill-over processes) and/or specific adsorption sites at the platinum-ceria interface. The main route for SOx release is found to be thermal decomposition where the effect of platinum is minor, although an indirect effect cannot be ruled out. Different mechanistic scenarios for SOx adsorption are discussed, which may serve as a guide for future experiments.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Catalysis
Authors
Markus Happel, Lisa Kylhammar, Per-Anders Carlsson, Jörg Libuda, Henrik Grönbeck, Magnus Skoglundh,