Journal ArticleDOI
A review of catalytic partial oxidation of methane to synthesis gas with emphasis on reaction mechanisms over transition metal catalysts
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In this article, an extensive table on contributions to catalytic partial oxidation of methane over transition metal catalysts in the literature is provided, and both theoretical and experimental evidence pointing to inherent differences in the reaction mechanism over transition metals.Abstract:
Catalytic partial oxidation of methane has been reviewed with an emphasis on the reaction mechanisms over transition metal catalysts. The thermodynamics and aspects related to heat and mass transport is also evaluated, and an extensive table on research contributions to methane partial oxidation over transition metal catalysts in the literature is provided. Presented are both theoretical and experimental evidence pointing to inherent differences in the reaction mechanism over transition metals. These differences are related to methane dissociation, binding site preferences, the stability of OH surface species, surface residence times of active species and contributions from lattice oxygen atoms and support species. Methane dissociation requires a reduced metal surface, but at elevated temperatures oxides of active species may be reduced by direct interaction with methane or from the reaction with H, H2, C or CO. The comparison of elementary reaction steps on Pt and Rh illustrates that a key factor to produce hydrogen as a primary product is a high activation energy barrier to the formation of OH. Another essential property for the formation of H2 and CO as primary products is a low surface coverage of intermediates, such that the probability of O–H, OH–H and CO–O interactions are reduced. The local concentrations of reactants and products change rapidly through the catalyst bed. This influences the reaction mechanisms, but the product composition is typically close to equilibrated at the bed exit temperature.read more
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Journal ArticleDOI
Endogenous Nanoparticles Strain Perovskite Host Lattice Providing Oxygen Capacity and Driving Oxygen Exchange and CH 4 Conversion to Syngas
TL;DR: This work shows that in the emergent nanostructure, the endogenous nanoparticles and the perovskite lattice become reciprocally strained and seamlessly connected, enabling enhanced oxygen exchange and demonstrates that deeply submerged, redox-active nanoparticles could be entirely accessible to reaction environments, driving redox transformations and thus offering intriguing new alternatives to design materials underpinning several energy conversion technologies.
Journal ArticleDOI
Heterogeneous partial oxidation catalysis on metal oxides
Jacques C. Védrine,Ioana Fechete +1 more
TL;DR: An overview of heterogeneous selective ammoxidation and oxidative dehydrogenation (ODH) of light alkanes, particularly of ethane, is presented in this article, where several case studies have been presented to illustrate the concept and importance of the key factors of catalyst preparation and activation and of the catalytic atmosphere.
Journal ArticleDOI
Partial Oxidation of Methane to Syngas Over γ-Al2O3-Supported Rh Nanoparticles: Kinetic and Mechanistic Origins of Size Effect on Selectivity and Activity
TL;DR: A series of supported Rh/γ-Al2O3 catalysts with an overall metal loading of 0.005 wt % was synthesized by impregnation of γ-Al 2O3 with a toluene solution containing colloidally prepared well-defined (1.1, 2.5), 2.9, 3.7, and 5.5 nm) Rh nanoparticles (NP).
Journal ArticleDOI
Renewable-powered hydrogen economy from Australia's perspective
TL;DR: In this paper, the main techno-economic enabler factors for Australia to transform and lead the regional energy market are identified, and two main categories for competitive and commercial-scale hydrogen production routes in Australia are identified: electrolysis powered by renewable, and fossil fuel cracking via steam methane reforming (SMR) or coal gasification which must be coupled with carbon capture and sequestration (CCS).
Book ChapterDOI
Utilization of Biogas as a Renewable Carbon Source: Dry Reforming of Methane
TL;DR: In this paper, the authors reviewed the chemistry of DRM and the catalytic systems developed for this process, with emphasis on the most important issue, namely, catalyst deactivation due to accumulation of carbonaceous deposits.
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Journal ArticleDOI
Production of Syngas by Direct Catalytic Oxidation of Methane
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Journal ArticleDOI
Microscopic view of epitaxial metal growth: nucleation and aggregation
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