Journal ArticleDOI
A review of catalytic partial oxidation of methane to synthesis gas with emphasis on reaction mechanisms over transition metal catalysts
Reads0
Chats0
TLDR
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
Citations
More filters
Journal ArticleDOI
Tracking dynamic structural changes in catalysis by rapid 2D-XANES microscopy.
Saba Alizadehfanaloo,Jan Garrevoet,Martin Seyrich,Vadim Murzin,Johannes Becher,Dmitry E. Doronkin,Thomas L. Sheppard,Jan-Dierk Grunwaldt,Christian G. Schroer,Andreas Schropp +9 more
TL;DR: In this paper, a high-resolution 2D X-ray camera operating at 50-Hz full-frame rate was synchronized with a QEXAFS monochromator, enabling rapid spectro-microscopic imaging with chemical contrast over individual pixels.
Journal ArticleDOI
Pt/Al2O3La2O3 catalysts stable at high temperature in air, prepared using a “one-pot” sol–gel process: Synthesis, characterization, and catalytic activity in the partial oxidation of CH4
TL;DR: In this article, the Pt/Al 2O3La2O3 catalysts were characterized by in situ X-ray absorption spectroscopy (XAS) and the partial oxidation of methane reaction was used to evaluate catalyst stability.
Selective Oxidation of Methane to CO on Ni@BOx via Reaction-induced Vapor Migration of Boron-containing Species onto Ni
Journal ArticleDOI
Analysis of the Fundamental Aspects of Oxidation of Rich Methane Mixtures in Matrix-Type Converters
TL;DR: In this article, the equilibrium distribution of oxidation products was calculated for the system СН4 + ψО2 → products at 0.5 0.6 and temperatures higher than 1000-1200 K (depending on ψ).
References
More filters
Journal ArticleDOI
CO2 Reforming of CH4
TL;DR: Although technological practice should minimize environmental impact, this is not always economically feasible as mentioned in this paper, and during the past decade, there has been increasing global concern over the environmental impact of technology.
Journal ArticleDOI
Kinetics and Selectivity of the Fischer–Tropsch Synthesis: A Literature Review
TL;DR: In this article, a critical review of the kinetics and selectivity of the Fischer-Tropsch synthesis (FTS) is given, focusing on reaction mechanisms and kinetics.
Journal ArticleDOI
Steam Reforming and Graphite Formation on Ni Catalysts
Hanne Skov Bengaard,Jens K. Nørskov,Jens Sehested,Clausen Bjerne Steffen,L.P. Nielsen,A.M. Molenbroek,Jens R. Rostrup-Nielsen +6 more
TL;DR: Based on density functional theory calculations, kinetic measurements, microkinetic and Monte Carlo simulations, thermogravimetric analysis (TGA) experiments, extended X-ray absorption spectroscopy (EXAFS) measurements, and experimental results from the literature, this paper presented a detailed and comprehensive mechanistic picture of the steam reforming process on a Ni catalyst.
Journal ArticleDOI
Production of Syngas by Direct Catalytic Oxidation of Methane
TL;DR: Rhodium was considerably superior to platinum in producing more H2 and less H2O, which can be explained by the known chemistry and kinetics of reactants, intermediates, and products on these surfaces.
Journal ArticleDOI
Microscopic view of epitaxial metal growth: nucleation and aggregation
TL;DR: In this article, the authors reviewed the early stages of epitaxial growth and showed how the growth kinetics can be employed to create well-defined island morphologies and island arrays in a self-organization process.