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  • Catalytic performance and stability of Fe-doped CeO 2 in propane oxidative dehydrogenation using carbon dioxide as an oxidant
Title: Catalytic performance and stability of Fe-doped CeO 2 in propane oxidative dehydrogenation using carbon dioxide as an oxidant
Propane oxidative dehydrogenation (ODH) in the presence of CO 2 was investigated over a series of Fe-doped CeO 2 catalysts. The well-recognized properties of cerium oxide materials regarding improved oxygen mobility and oxygen storage capacity (OSC) were utilized towards the synthesis of stable catalytic systems. The iron–cerium oxide solid solution catalysts with an Fe dopant content from 1% up to 15% were successfully synthesized via a co-precipitation method and calcined at 873 K. It was confirmed by XRD and Raman characterization that all samples featured a single cerianite crystalline phase with periodic lattice Ce ions substituted by Fe ions, with no hematite phase identified. Initial screening of catalytic behavior showed that the propane ODH pathway was enhanced at high Fe/Ce ratio while propane cracking was suppressed. Stable propane conversion and propylene selectivity for up to 20 hours were achieved for the synthesized catalysts with moderate Fe loading. Ex situ Raman, XPS and STEM were applied to analyze post-reaction catalysts and confirmed that deactivation occurring over low Fe catalysts resulted from coke deposition on the surface, while CeO 2 sintering and Fe migration to form nanocrystals were the primary deactivation reasons for high Fe loading catalysts.  more » « less
Award ID(s):
1751683
PAR ID:
10197436
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Catalysis Science & Technology
Volume:
10
Issue:
13
ISSN:
2044-4753
Page Range / eLocation ID:
4362 to 4372
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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