Sökning: "Chabazite"
Hittade 5 avhandlingar innehållade ordet Chabazite.
1. On the Character of Active Sites in Copper Exchanged Zeolites during NH3-SCR
Sammanfattning : Nitrogen oxides (NOx) are formed during combustion in diesel engines and one current approach to reduce NOx to N2 is selective catalytic reduction with NH3 as reducing agent (NH3-SCR). To acquire both high activity and selectivity, the active site is often atomically dispersed metal atom, so-called single-site catalysts. LÄS MER
2. Partial Oxidation of Methane over Functionalised Zeolites and Zeotypes
Sammanfattning : Partial oxidation of methane to methanol is an industrially important process that allows natural gas and biogas to be utilised for methanol-based production of chemicals or converted to liquid methanol fuel, which make transportation more facile. In this thesis, the activity for partial oxidation of methane to methanol over copper functionalised zeolites and silica supported copper is investigated using a three-step quasi-catalytic approach including catalyst activation, methane reaction and methanol extraction by water. LÄS MER
3. Dynamics and Reactivity of Cu-species in Cu-CHA for NH3-SCR
Sammanfattning : Copper exchanged chabazite (Cu-CHA) is a state-of-the-art catalyst for deNOx via ammonia assisted selective catalytic reduction (NH3-SCR) in lean burn engines, owing to its good low-temperature activity, and high hydrothermal stability. One challenge for Cu-CHA is, however, the sensitivity to sulfur species, which are present in the exhaust gas. LÄS MER
4. Reaction kinetics of NH3-SCR over Cu-CHA from first principles
Sammanfattning : Ammonia-assisted selective catalytic reduction (NH3-SCR) is an advanced technology to reduce nitrogen oxide (NOx) emissions from lean-burn engines. NH3 is added to the exhaust gas and reacts selectively with NOx, forming N2 and H2O. LÄS MER
5. Reactions on nanostructured and microporous surfaces
Sammanfattning : Interactions between surfaces and molecules play a central role in various fields where catalysis is one example. In order to understand different surface processes, physicochemical characterisation of the surface materials and molecules is required. LÄS MER