Transient infrared study of methanation and ethylene hydroformylation over Rh/SiO[sub 2] catalysts

Journal Article · Mon Mar 01 00:00:00 EST 1993 · Journal of Catalysis; (United States)

DOI:https://doi.org/10.1006/jcat.1993.1083· OSTI ID:6305002

Balakos, M W; Chuang, S S.C.; Srinivas, G ^[1]

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1. Univ. of Akron, OH (United States)

Determination of reactivity and surface coverage of intermediates has been a challenging goal in fundamental research of heterogeneous catalysis. First Happel et al. and later Biloen and co-workers employed the use of a transient rate tracer method for the determination of the intrinsic rate constant, k, and the fractional surface coverage, [Theta], of intermediates for steady-state carbon monoxide hydrogenation. The method was further developed and termed steady-state isotopic transient kinetic analysis (SSITKA) by Goodwin and co-workers. SSITKA is a transient method for the investigation of kinetics and mechanism of heterogeneous catalysis under steady-state conditions. The approach involves an abrupt switch from an inlet reactant species to a corresponding isotopically labeled species. The advantage of SSITKA from other transient methods is that the chemical environment of the catalyst surface does not vary with the transient state of the isotopic tracer, yielding tracer response curves for the determination of k and [Theta]. The method has been applied in the investigation of the mechanism of methanation, Fischer-Tropsch synthesis, ammonia synthesis, and partial oxidation of methane. In situ infrared absorption spectroscopy (IR) allows for the direct observation of absorbed species under reaction conditions. Incorporation of in situ IR spectroscopy with SSITKA may provide information on the surface coverages of IR observable species under reaction conditions and has the potential for distinguishing between reaction intermediates and surface absorbed spectator species. This paper reports the use of IR combined with SSITKA to study methanation and ethylene hydroformylation on Rh/SiO[sub 2] at 513 K and 0.1 MPa. 20 refs., 3 figs.

• OSTI ID: 6305002
• Journal Information: Journal of Catalysis; (United States), Vol. 140:1; ISSN 0021-9517
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
02 PETROLEUM
01 COAL, LIGNITE, AND PEAT
CARBON MONOXIDE
METHANATION
ETHYLENE
CARBONYLATION
RHODIUM COMPOUNDS
CATALYTIC EFFECTS
SILICON OXIDES
ABSORPTION SPECTROSCOPY
CATALYSTS
CHEMICAL REACTION KINETICS
HETEROGENEOUS CATALYSIS
REACTION INTERMEDIATES
STEADY-STATE CONDITIONS
ALKENES
CARBON COMPOUNDS
CARBON OXIDES
CATALYSIS
CHALCOGENIDES
CHEMICAL REACTIONS
HYDROCARBONS
KINETICS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
REACTION KINETICS
REFRACTORY METAL COMPOUNDS
SILICON COMPOUNDS
SPECTROSCOPY
TRANSITION ELEMENT COMPOUNDS
400201* - Chemical & Physicochemical Properties
020400 - Petroleum- Processing
010408 - Coal
Lignite
& Peat- C1 Processes- (1987-)