Nazimov, Daniil A.;
Klimov, Oleg V.;
Trukhan, Sergey N.;
Cherepanova, Svetlana V.;
Prosvirin, Igor P.;
Noskov, Aleksandr S.
The Effect of Transition Alumina (γ‐, η‐, χ‐Al2O3) on the Activity and Stability of Chromia/Alumina Catalysts. Part I: Model Catalysts and Aging Conditions
Sie können Bookmarks mittels Listen verwalten, loggen Sie sich dafür bitte in Ihr SLUB Benutzerkonto ein.
Medientyp:
E-Artikel
Titel:
The Effect of Transition Alumina (γ‐, η‐, χ‐Al2O3) on the Activity and Stability of Chromia/Alumina Catalysts. Part I: Model Catalysts and Aging Conditions
Beteiligte:
Nazimov, Daniil A.;
Klimov, Oleg V.;
Trukhan, Sergey N.;
Cherepanova, Svetlana V.;
Prosvirin, Igor P.;
Noskov, Aleksandr S.
Erschienen:
Wiley, 2019
Erschienen in:
Energy Technology, 7 (2019) 4
Sprache:
Englisch
DOI:
10.1002/ente.201800735
ISSN:
2194-4288;
2194-4296
Entstehung:
Anmerkungen:
Beschreibung:
The effect of transition alumina (γ‐, η‐, χ‐Al2O3) on the activity and stability of model chromia/alumina catalysts with 4 wt% Cr in isobutane dehydrogenation is studied. It is shown that a fresh catalyst with η‐Al2O3as a support has the highest activity, while with χ‐Al2O3has the lowest one. The characterization of the catalysts by N2adsorption, X‐ray diffraction (XRD), electron spin resonance (ESR) spectroscopy, and X‐ray photoelectron spectroscopy (XPS) is used to describe changes in the catalysts induced by high‐temperature treatment at 800, 1000, and 1200 °C in air. It is shown that sintering of the alumina support and formation of chromia‐alumina solid solutions are the reasons of irreversible decline in the catalytic activity. Cr/γ‐Al2O3is found to be the most stable to sintering and phase transformation, whereas Cr/χ‐Al2O3is found to be the least stable. Due to its highest initial activity, the η‐Al2O3‐supported catalyst loses its dehydrogenation activity most rapidly as the calcination temperature is raised. The segregation of sodium impurities is observed in the course of heat treatment, which may be an additional cause of deactivation.