Effects of ionic promoters on CO dissociation and CO insertion on rhodium catalysts

Conference · Fri Feb 28 23:00:00 EST 1986 · Am. Chem. Soc., Div. Pet. Chem., Prepr.; (United States)

OSTI ID:5666997

Sachtler, W M.H.; Ichikawa, M

Hydrocarbons are the major product of CO hydrogenation on unpromoted Rh/SiO/sub 2/, prepared by decomposing Rh/sub 4/(CO)/sub 12/. More than 90% of methanol is formed after adding basic promoters such as ZnO. The formation of higher alcohols and aldehydes is promoted by adding oxophilic promoters (Mn, Zr, La, Nd, Nb). We have studied the interaction of Rh with the promoting ions and co-adsorbed CO using FTIR, EXAFS, Mossbauer, etc. Syngas conversion and ethylene hydroformulation were used to test for CO insertion and CO dissociation. These conclusions are: 1) Basic promoters block Freundlich sites on Rh, needed for bridging adsorption of CO. Rh surface atoms then act as individual atoms rather than as part of larger ensembles. This strongly enhances the hydroformylation selectivity. 2) Oxophilic promoters interact with the O atom of co-adsorbed CO, weakening the C=O bond and promoting CO dissociation.

• Research Organization: Ipatieff Lab., Dept. of Chemistry Northwestern Univ., Evanston, IL
• OSTI ID: 5666997
• Report Number(s): CONF-860425-
• Journal Information: Am. Chem. Soc., Div. Pet. Chem., Prepr.; (United States), Journal Name: Am. Chem. Soc., Div. Pet. Chem., Prepr.; (United States) Vol. 31:1; ISSN ACPCA
• Country of Publication: United States
• Language: English

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10 SYNTHETIC FUELS
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
ABSORPTION SPECTROSCOPY
ADSORPTION
ALCOHOLS
ALDEHYDES
ALKENES
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CATALYSTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL PREPARATION
CHEMICAL REACTIONS
DISSOCIATION
ELEMENTS
ETHYLENE
FLUIDS
GASES
HYDROCARBONS
HYDROGENATION
HYDROXY COMPOUNDS
METALS
METHANOL
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PLATINUM METALS
RHODIUM
SILICON COMPOUNDS
SILICON OXIDES
SORPTION
SPECTROSCOPY
SYNTHESIS
SYNTHESIS GAS
TESTING
TRANSITION ELEMENTS
ZINC COMPOUNDS
ZINC OXIDES