Deactivating Carbon Formation on a Ni/Al2O3 Catalyst under Methanation Conditions
| Autor: | Sine Ellemann Olesen, Christian Danvad Damsgaard, Klas Andersson, Ib Chorkendorff |
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| Rok vydání: | 2017 |
| Předmět: |
Inorganic chemistry
chemistry.chemical_element 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials Carbide Catalysis Nickel General Energy Adsorption chemistry Polymerization Methanation Physical and Theoretical Chemistry Linear correlation 0210 nano-technology Carbon |
| Zdroj: | The Journal of Physical Chemistry C. 121:15556-15564 |
| ISSN: | 1932-7455 1932-7447 |
| Popis: | The carbon formation causing deactivation during CO methanation was studied for a Ni/Al2O3 catalyst. Sulfur-free methanation at low temperature (573 K) for various lengths of time was followed by temperature-programmed hydrogenation (TPH) providing information on carbon types involved in the deactivation of the catalyst. Three main carbon hydrogenation peaks were evident from TPHs following methanation: ∼460, ∼650, and ∼775 K. It is suggested that the ∼460 K TPH peak was composed of two peaks: a surface carbide peak at 445–460 K, and a peak due to carbon dissolved into the nickel at 485 K based on CO and CH4 adsorption measurements and XRD analysis. The 650 and 775 K temperature peaks are assigned to polymerized carbon structures and the ∼775 K peak was found to be the primary cause of deactivation as judged by a linear correlation between its amount and the degree of catalyst deactivation. The longer the duration of the methanation test, the more carbon was built up on the Ni surfaces and the highest obs... |
| Databáze: | OpenAIRE |
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