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 · Thu Feb 01 00:00:00 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), Vol. 121:2; ISSN 0021-9517
• Country of Publication: United States
• Language: English

Related Subjects

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