Effect of Dithering on Post-Catalyst Exhaust Gas Composition and on Short Time Regeneration of Deactivated PdO/Al2O3 Catalysts under Real Engine Conditions KIT Karlsruhe Institute Of Technology

Format:

Book

Conference/Event

Author/Creator:

Tomin, Sebastian, author.

Contributor:

Koch, Thomas

Wagner, Uwe

Conference Name:

CO2 Reduction for Transportation Systems Conference (2024-06-12 : Turin, Italy)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 2024

Summary:

Fossil fuels such as natural gas used in engines still play an important role worldwide which however is also exacerbating climate change as a result of carbon dioxide emissions. Although natural gas engines show an overall low pollutant emissions level, methane slip due to incomplete combustion occurs, causing methane emissions with a more than 20 times higher global warming potential than CO2. Additionally, further tightening of emissions legislation is to be expected bringing methane emissions even more into focus making exhaust gas aftertreatment issues remain relevant. For lean gas applications, (Pd)-based catalysts turned out to convert CH4 most efficiently usually being supported by metal oxides such as aluminium oxide (Al2O3). Water (H2O) contained in the exhaust gas causes strong inhibition on Pd catalysts. In real exhaust gases, not only water vapour but also pollutants and sulphur-containing compounds such as hydrogen sulphide (H2S) or sulphur oxides (SOx) are poisoning the catalytic converter. Rich pulses decomposing sulphur species adsorbed on Pd-Pt methane oxidation catalysts, enable efficient regeneration of heavily poisoned catalysts. A strategy similar to operation with rich pulses, but with a different motivation, is the use of high-frequency oscillations between lean and rich exhaust gas, so-called dithering, to improve pollutant conversion. A combination of a stoichiometric pulse while simultaneously dithering shows better results in recovery as well as emissions during regeneration than a pure rich pulse

Notes:

Vendor supplied data

Publisher Number:

2024-37-0002

Access Restriction:

Restricted for use by site license