Oxidation of methane over supported precious metal catalysts

Journal Article · Sat Oct 01 00:00:00 EDT 1983 · J. Catal.; (United States)

DOI:https://doi.org/10.1016/0021-9517(83)90054-4· OSTI ID:5648002

Cullis, C F ^[1]; Willatt, B M

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1. City Univ., London, England

Studies of the kinetics of methane oxidation over palladium (Pd) and platinum (Pt) catalysts supported on a number of metal oxides were made using a pulse-flow microreactor technique. The reaction was investigated at temperatures in the range 500 to 800 K using reactant mixtures with CH/sub 4/:O/sub 2/ ratios varying from 1:10 to 10:1. The supports themselves, with the exception of tin(IV) oxide, did not appreciably catalyze the oxidation reaction. Nevertheless, the activity of both Pd and Pt catalysts was enhanced by the use of metal oxides of large surface area, such as ..gamma..-aluminum(III) oxide (Al/sub 2/O/sub 3/). The support also influenced the ability of Pd to adsorb oxygen and there was a correlation between the adsorption capacity of the supported precious metal and its catalytic activity for methane oxidation. The presence of adsorbed oxygen was confirmed using x-ray photoelectron spectroscopy but oxygen adsorbed at high temperatures proved detrimental towards methane oxidation. Prolonged exposure of the precious metals to oxygen at high temperatures caused structural changes in Pd, although this did not occur with Pt. The different catalytic behaviour of Pd and Pt was attributed to the differing abilities of these precious metals to adsorb oxygen prior to reaction. Measurement by transmission electron microscopy of the diameters of Pd particles dispersed on a ..gamma..-Al/sub 2/O/sub 3/ oxide support showed that the catalytic activity for methane oxidation was independent of particle size. 7 figures, 9 tables.

• OSTI ID: 5648002
• Journal Information: J. Catal.; (United States), Journal Name: J. Catal.; (United States) Vol. 83:2; ISSN JCTLA
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
034000* -- Natural Gas-- Combustion
36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400104 -- Spectral Procedures-- (-1987)
400301 -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
ABSORPTION SPECTROSCOPY
ACTINIDE COMPOUNDS
ACTIVATION ENERGY
ADSORPTION
ALKANES
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
BINDING ENERGY
CALORIMETRY
CATALYST SUPPORTS
CATALYSTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL ANALYSIS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CHROMATOGRAPHY
DATA
ELECTRON MICROSCOPY
ELECTRON SPECTROSCOPY
ELEMENTS
ENERGY
EXPERIMENTAL DATA
FLUIDS
GAS CHROMATOGRAPHY
GASES
HELIUM
HIGH TEMPERATURE
HYDROCARBONS
INFORMATION
KINETICS
METALS
METHANE
MICROSCOPY
MONITORING
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
OXIDES
OXYGEN
OXYGEN COMPOUNDS
PALLADIUM
PARTICLE SIZE
PHOTOELECTRON SPECTROSCOPY
PLATINUM
PLATINUM METALS
POWDERS
PULSE TECHNIQUES
QUANTITATIVE CHEMICAL ANALYSIS
RARE GASES
REACTION KINETICS
SEPARATION PROCESSES
SIZE
SORPTION
SORPTIVE PROPERTIES
SPECTROSCOPY
STRUCTURAL CHEMICAL ANALYSIS
SURFACE AREA
SURFACE PROPERTIES
TEMPERATURE DEPENDENCE
THORIUM COMPOUNDS
THORIUM OXIDES
TIN COMPOUNDS
TIN OXIDES
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
TRANSMISSION ELECTRON MICROSCOPY