Rhodium-carbon monoxide surface chemistry: the involvement of surface hydroxyl groups on Al/sub 2/O/sub 3/ and SiO/sub 2/ supports

Journal Article · Wed Mar 30 00:00:00 EST 1988 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00215a010· OSTI ID:7200315

Basu, P; Panayotov, D; Yates, Jr, J T

Direct spectroscopic evidence has been obtained indicating that specific OH groups on Al/sub 2/O/sub 3/ and SiO/sub 2/ are consumed as CO interacts with supported Rh crystallites to produce atomically dispersed Rh/sup I/(CO)/sub 2/(a). The reaction (1/x)Rh/sub x//sup 0/ + OH(a) + 2CO(g) ..-->.. Rh/sup I/(CO)/sub 2/(a) + (1/2)H/sub 2/(g) has been shown to involve isolated OH(a) groups rather than H-bonded associated OH(a) species. The process may also be reversed upon treatment of the chemisorbed CO layer with H/sub 2/(g) at temperatures above approx. 200 K. With the H/sub 2/ treatment, Rh/sup I/(CO)/sub 2/(a) species are converted back to Rh/sub x//sup 0/ species as judged by changes in the IR spectrum where terminal CO(a) species (on Rh/sub x//sup 0/ sites) and isolated OH(a) groups are regenerated. Comparative kinetic studies of OH(a) and OD(a) species indicate that the rate controlling step in the production of Rh/sup I/(CO)/sub 2/(a) does not exhibit a measurable kinetic isotope effect.

• Research Organization: Univ. of Pittsburgh, PA (USA)
• OSTI ID: 7200315
• Journal Information: J. Am. Chem. Soc.; (United States), Vol. 110:7
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CARBON MONOXIDE
CHEMISORPTION
RHODIUM
CATALYTIC EFFECTS
SORPTIVE PROPERTIES
SURFACE PROPERTIES
ALUMINIUM OXIDES
ANIONS
CATALYSIS
CATALYST SUPPORTS
CATALYSTS
CHEMICAL REACTION KINETICS
EXPERIMENTAL DATA
HYDROXIDES
INFRARED SPECTRA
SILICA
SURFACES
TEMPERATURE DEPENDENCE
ALUMINIUM COMPOUNDS
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CHARGED PARTICLES
CHEMICAL REACTIONS
DATA
ELEMENTS
HYDROGEN COMPOUNDS
INFORMATION
IONS
KINETICS
METALS
MINERALS
NUMERICAL DATA
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PLATINUM METALS
REACTION KINETICS
SEPARATION PROCESSES
SILICON COMPOUNDS
SILICON OXIDES
SORPTION
SPECTRA
TRANSITION ELEMENTS
400201* - Chemical & Physicochemical Properties