Effect of SMSI (strong metal-support interaction) behavior on CO adsorption and hydrogenation on Pd catalysts. II. Kinetic behavior in the methanation reaction

Journal Article · Tue Sep 01 04:00:00 EDT 1981 · J. Catal.; (United States)

DOI:https://doi.org/10.1016/0021-9517(81)90212-8· OSTI ID:6026396

Wang, S Y; Moon, S H; Vannice, M A

The specific activity of Pd in the methanation reaction can show a 200-fold variation depending upon the support used. In contrast, the CH/sub 4/ turnover frequency is independent of Pd crystallite size, at least over the range of 3 to 30 nm particles. The most active catalyst is TiO/sub 2/-supported Pd in which an SMSI state has been induced, and silica-supported Pd is the least active. Turnover numbers increase in the following order: Pd/SiO/sub 2/ < Pd/SiO/sub 2/-Al/sub 2/O/sub 3/, Pd/Al/sub 2/O/sub 3/ approx. = Pd/TiO/sub 2/ (448 K) < Pd/TiO/sub 2/ (SMSI). All CO partial pressure dependencies were near zero, while H/sub 2/ partial pressure dependencies shifted from unity to near one-half for the TiO/sub 2/-supported catalysts. A reaction model for Pd is proposed which is consistent with this behavior, with ir spectra of CO adsorbed on these Pd surfaces, and with recent results in the literature on CO hydrogenation. This model involves no assumptions regarding CO coverage, and assumes CH/sub 4/ forms from surface carbon produced by a hnsities on the Pd/TiO/sub 2/ catalysts, even at 300 K. The effect of Pd on the activity of CuO.

• Research Organization: Pennsylvania State Univ., University Park
• OSTI ID: 6026396
• Journal Information: J. Catal.; (United States), Journal Name: J. Catal.; (United States) Vol. 71:1; ISSN JCTLA
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404* -- Coal
Lignite
&amp; Peat-- Gasification
090121 -- Hydrocarbon Fuels-- Chemical Synthesis-- (1976-1989)
10 SYNTHETIC FUELS
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical &amp; Physicochemical Properties
ADSORPTION
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CATALYST SUPPORTS
CATALYSTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL REACTIONS
COMPARATIVE EVALUATIONS
DATA
ELEMENTS
EXPERIMENTAL DATA
HYDROGENATION
INFORMATION
INFRARED SPECTRA
METALS
METHANATION
MINERALS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PALLADIUM
PARTICLE SIZE
PLATINUM METALS
SILICA
SILICON COMPOUNDS
SILICON OXIDES
SIZE
SORPTION
SORPTIVE PROPERTIES
SPECTRA
SURFACE PROPERTIES
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS