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Title: Methane activation by ZSM-5-supported transition metal centers
This review focuses on recent fundamental insights about methane dehydroaromatization (MDA) to benzene over ZSM-5-supported transition metal oxide-based catalysts (MO x /ZSM-5, where M = V, Cr, Mo, W, Re, Fe). Benzene is an important organic intermediate, used for the synthesis of chemicals like ethylbenzene, cumene, cyclohexane, nitrobenzene and alkylbenzene. Current production of benzene is primarily from crude oil processing, but due to the abundant availability of natural gas, there is much recent interest in developing direct processes to convert CH 4 to liquid chemicals. Among the various gas-to-liquid methods, the thermodynamically-limited Methane DehydroAromatization (MDA) to benzene under non-oxidative conditions appears very promising as it circumvents deep oxidation of CH 4 to CO 2 and does not require the use of a co-reactant. The findings from the MDA catalysis literature is critically analyzed with emphasis on in situ and operando spectroscopic characterization to understand the molecular level details regarding the catalytic sites before and during the MDA reaction. Specifically, this review discusses the anchoring sites of the supported MO x species on the ZSM-5 support, molecular structures of the initial dispersed surface MO x sites, nature of the active sites during MDA, reaction mechanisms, rate-determining step, kinetics and catalyst activity of the MDA reaction. Finally, suggestions are given regarding future experimental investigations to fill the information gaps currently found in the literature.  more » « less
Award ID(s):
1706581
PAR ID:
10356413
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Chemical Society Reviews
Volume:
50
Issue:
2
ISSN:
0306-0012
Page Range / eLocation ID:
1251 to 1268
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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