Oxygen sorption and catalytic properties of La sub 1 minus x Sr sub x Co sub 1 minus y Fe sub y O sub 3 perovskite-type oxides

Journal Article · Wed Jan 31 23:00:00 EST 1990 · Journal of Catalysis; (USA)

DOI:https://doi.org/10.1016/0021-9517(90)90251-E· OSTI ID:6379180

Zhang, H M; Shimizu, Y; Miura, N; Yamazoe, N ^[1]; Teraoka, Y ^[2]

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1. Kyushu Univ., Fukuoka (Japan)
2. Nagasaki Univ. (Japan)

Oxygen desorption from La{sub 1{minus}x}Sr{sub x}Co{sub 1{minus}y}Fe{sub y}O{sub 3} perovskite-type oxides below 850{degree}C was examined by a temperature-programmed desorption (TPD) technique. The catalytic activities of the oxides for the combustion of n-butane and methane as well as H{sub 2}O{sub 2} decomposition in an alkaline solution were also measured and were discussed in relation to oxygen sorption properties. The amount of oxygen desorbed increased with increasing Sr content at a fixed B-site composition, for which an increase in the number of oxide ion vacancies with x was responsible. On the other hand, the total amount of oxygen desorbed was hardly affected by B-site composition, but partial substitution of Fe for Co enhanced desorption and sorption of oxygen particularly in the low-temperature region. Substitution of Sr for La as well as of Fe for Co was found to promote catalytic activity, though the activity changed with oxide composition in a manner dependent on the kind of reactant. For n-butane combustion over La{sub 1{minus}x}Sr{sub x}Co{sub 0.4}Fe{sub 0.6}O{sub 3}, maximum activity was obtained at x = 0.2. La{sub 0.2}Sr{sub 0.8}Co{sub 1{minus}y}Fe{sub y}O{sub 3} activity was highest at y = 0.4 for n-butane combustion, while it was independent of y for methane combustion. For H{sub 2}O{sub 2} decomposition in an alkaline solution, on the other hand, La{sub 1{minus}x}Sr{sub x}Co{sub 0.4}Fe{sub 0.6}O{sub 3} and La{sub 1{minus}x}Sr{sub x}CoO{sub 3} activities increased monotonically with an increase in x, and the former oxides were more active than the latter. These variations in catalytic activities with oxide composition were well accounted for by the oxygen sorption properties revealed by TPD.

• OSTI ID: 6379180
• Journal Information: Journal of Catalysis; (USA), Journal Name: Journal of Catalysis; (USA) Vol. 121:2; ISSN 0021-9517; ISSN JCTLA
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
025000 -- Petroleum-- Combustion
03 NATURAL GAS
034000 -- Natural Gas-- Combustion
33 ADVANCED PROPULSION SYSTEMS
330702 -- Emission Control-- Carbon Monoxide
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALKALINE EARTH METAL COMPOUNDS
ALKANES
BUTANE
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CATALYSTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
COBALT COMPOUNDS
COBALT OXIDES
COMBUSTION
CONTROL
DECOMPOSITION
DESORPTION
ELEMENTS
HIGH TEMPERATURE
HYDROCARBONS
HYDROGEN COMPOUNDS
HYDROGEN PEROXIDE
IRON COMPOUNDS
IRON OXIDES
LANTHANUM COMPOUNDS
LANTHANUM OXIDES
MATERIAL SUBSTITUTION
METHANE
NONMETALS
ORGANIC COMPOUNDS
OXIDATION
OXIDES
OXYGEN
OXYGEN COMPOUNDS
PEROVSKITES
PEROXIDES
QUANTITY RATIO
RARE EARTH COMPOUNDS
SORPTION
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SURFACE PROPERTIES
TEMPERATURE CONTROL
THERMOCHEMICAL PROCESSES
TRANSITION ELEMENT COMPOUNDS