Abstract
For commercialization, alcohol-based net-zero carbon fuels in diesel-driven internal combustion engines must meet emissions standards set by the U.S. Environmental Protection Agency. A series of aged commercial oxidation catalysts, Pt diesel oxidation catalyst (DOC), Pd+Pt DOC, and Pt oxidation catalyst (Pt OC), were studied using an automated flow reactor and in situ DRIFTS techniques to investigate the impact of CO on alcohol oxidation. Surface formate and acetate intermediates were formed due to partial oxidation of methanol and ethanol, respectively. Sequential introduction of alcohol and CO experiments using in situ DRIFTS on all three catalysts showed that CO inhibited low temperature methanol oxidation. Mutual inhibition effects between CO and ethanol were observed during co-oxidation. Acetate species shifted CO oxidation to higher temperatures on Pt DOC and Pt OC, whereas CO pre-exposure inhibited acetate formation. CO oxidation occurred at lower temperatures during ethanol and CO co-oxidation on Pd+Pt DOC.
| Original language | English |
|---|---|
| Article number | 125402 |
| Journal | Applied Catalysis B: Environmental |
| Volume | 375 |
| DOIs | |
| State | Published - Oct 15 2025 |
Funding
This research was supported by the U.S. Department of Energy (DOE), Office of Energy Efficiency and Renewable Energy (EERE) and Vehicle Technologies Office (VTO) and used resources at the National Transportation Research Center, a DOE-EERE User Facility at Oak Ridge National Laboratory. The authors gratefully acknowledge guidance and support from Nicholas Hansford, Siddiq Khan, Kevin Stork, and Gurpreet Singh at DOE VTO. The authors also acknowledge the discussions and guidance from Dave Montgomery, Kenth Svennson, and Josh Ratts at Caterpillar Inc. The authors also acknowledge the catalyst sample from Joseph Fedeyko and Feiyang Geng at Johnson Matthey.
Keywords
- CO inhibition
- DRIFTS
- Emission control
- Methanol and ethanol oxidation
- Oxidation catalyst