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Ethylene oxidation by Ag catalysts has been extensively investigated over the past few decades, but many key fundamental issues about this important catalytic system are still unresolved. This overview of the selective oxidation of ethylene to ethylene oxide by Ag catalysts critically examines the experimental and theoretical literature of this complex catalytic system: (i) the surface chemistry of silver catalysts (single crystal, powder/foil, and supported Ag/α-Al2O3), (ii) the role of promoters, (iii) the reaction kinetics, (iv) the reaction mechanism, (v) density functional theory (DFT), and (vi) microkinetic modeling. Only in the past few years have the modern catalysis research tools of in situ/operando spectroscopy and DFT calculations been applied to begin establishing fundamental structure−activity/selectivity relationships. This overview of the ethylene oxidation reaction by Ag catalysts covers what is known and what issues still need to be determined to advance the rational design of this important catalytic system.
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This content will become publicly available on August 1, 2026
Oxidative dehydrogenation of ethane (ODHE) to ethylene by bulk MoVNbTe mixed oxide M1 phase catalysts
The conversion of ethane to ethylene by steam cracking is an energy-intensive process that also produces significant global warming CO2 emissions. An alternative process that is not as energy-intensive and produces significantly less CO2 emissions is the oxidative dehydrogenation of ethane to ethylene by the bulk MoVNbTe mixed oxide catalyst. This paper reviews the current understanding of this catalytic reaction system to determine the nature of the bulk and surface phases of this important catalytic reaction. Although the crystalline M1 phase represents the bulk active phase, much is still unknown about the catalytic active surface sites of the M1 phase under reaction conditions. This review extensively examines the reported studies to date and outlines the experiments still needed to establish a fundamental structure-activity/selectivity relationship for this catalytic system that will guide the development of improved catalysts.
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- Award ID(s):
- 2221714
- PAR ID:
- 10654514
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Applied Catalysis B: Environment and Energy
- Volume:
- 371
- Issue:
- C
- ISSN:
- 0926-3373
- Page Range / eLocation ID:
- 125194
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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