Regeneration of model supported metal catalysts
Journal Article
·
· J. Catal.; (United States)
Regeneration of a model catalyst of Pt over ..gamma..-Al/sub 2/O/sub 3/ was studied as a function of time using a TEM. The decrease in particle diameter was accomplished by heating the sample in air at 500/sup 0/C for times up to 2 h. The results were analyzed using a model which is shown to be particularly valid for short times and large particle sizes. The model postulates a surface layer of oxide on the supported metal particle. The difference between Pt-Pt distances in the surface layer of platinum oxide and in the unoxidized metal gives rise to forces which may crack and split the particle. The experimental results indicate that the initial regeneration rate is rapid, and that the rate falls off after about 2 h of heating. Applying the model to the experimental data yields values for an average rate of oxidation of 2.37 nm/h, and a minimum particle diameter for crack initiation of 8.6 nm. These values are consistent with numbers obtained for these parameters from completely different circumstances.
- Research Organization:
- Rensselaer Polytechnic Inst., Troy, NY
- OSTI ID:
- 6414513
- Journal Information:
- J. Catal.; (United States), Journal Name: J. Catal.; (United States) Vol. 68:2; ISSN JCTLA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Regeneration of model supported metal catalysts
Effects of particle size on the progressive oxidation of nanometer platinum by dioxygen
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Conference
·
Sun Dec 31 23:00:00 EST 1978
· 72nd AIChE Annu. Meet. Prepr.; (United States)
·
OSTI ID:6187674
Effects of particle size on the progressive oxidation of nanometer platinum by dioxygen
Journal Article
·
Thu Sep 10 00:00:00 EDT 1998
· Journal of Catalysis
·
OSTI ID:659086
Catalytic cracking using a cracking catalyst in admixture with particles of platinum group metal or rhenium on a substrate regenerated to up to about 0. 1% coke
Patent
·
Mon Mar 05 23:00:00 EST 1984
·
OSTI ID:6803201
Related Subjects
02 PETROLEUM
020400* -- Petroleum-- Processing
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CATALYST SUPPORTS
CATALYSTS
CHALCOGENIDES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CRACKING
DECOMPOSITION
DEHYDROGENATION
ELECTRON MICROSCOPY
ELEMENTS
HEAT TREATMENTS
HIGH TEMPERATURE
HYDROCARBONS
HYDROCRACKING
ISOMERIZATION
KINETICS
METALS
MICROSCOPY
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PARTICLE SIZE
PLATINUM
PLATINUM COMPOUNDS
PLATINUM METALS
PLATINUM OXIDES
PYROLYSIS
REACTION KINETICS
REGENERATION
SIZE
SURFACES
THERMOCHEMICAL PROCESSES
TIME DEPENDENCE
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
020400* -- Petroleum-- Processing
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CATALYST SUPPORTS
CATALYSTS
CHALCOGENIDES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CRACKING
DECOMPOSITION
DEHYDROGENATION
ELECTRON MICROSCOPY
ELEMENTS
HEAT TREATMENTS
HIGH TEMPERATURE
HYDROCARBONS
HYDROCRACKING
ISOMERIZATION
KINETICS
METALS
MICROSCOPY
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PARTICLE SIZE
PLATINUM
PLATINUM COMPOUNDS
PLATINUM METALS
PLATINUM OXIDES
PYROLYSIS
REACTION KINETICS
REGENERATION
SIZE
SURFACES
THERMOCHEMICAL PROCESSES
TIME DEPENDENCE
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS