The effect of additives on the reactivity of palladium surfaces for the chemisorption and hydrogenation of carbon monoxide: A surface science and catalytic study. [LaMO/sub 3/(M = Cr, Mn, Fe, Co, Rh)]

Technical Report · Mon Jun 01 04:00:00 EDT 1987

DOI:https://doi.org/10.2172/6389716· OSTI ID:6389716

Rucker, T G

This research studied the role of surface additives on the catalytic activity and chemisorptive properties of Pd single crystals and foils. Effects of Na, K, Si, P, S, and Cl on the bonding of CO and H and on the cyclotrimerization of acetylene on the (111), (100) and (110) faces of Pd were investigated in addition to role of TiO/sub 2/ and SiO/sub 2/ overlayers deposited on Pd foils in the CO hydrogenation reaction. On Pd, only in the presence of oxide overlayers, are methane or methanol formed from CO and H/sub 2/. The maximum rate of methane formation is attained on Pd foil where 30% of the surface is covered with titania. Methanol formation can be achieved only if the TiO/sub x//Pd surface is pretreated in 50 psi of oxygen at 550/sup 0/C prior to the reaction. The additives (Na, K, Si, P, S, Cl) affect the bonding of CO and hydrogen and the cyclotrimerization of acetylene to benzene by structural and electronic interactions. In general, the electron donating additives increase the desorption temperature of CO and increase the rate of acetylene cyclotrimerization and the electron withdrawing additives decrease the desorption temperature of CO and decrease the rate of benzene formation from acetylene.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6389716
• Report Number(s): LBL-23804; ON: DE87014685
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ACETYLENE
ADDITIVES
ALCOHOLS
ALKALI METALS
ALKANES
ALKYNES
AROMATICS
AUGER ELECTRON SPECTROSCOPY
BENZENE
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CATALYSTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL PREPARATION
CHEMICAL REACTIONS
CHEMISORPTION
CHLORINE
COHERENT SCATTERING
CONTAINERS
CRYSTALS
DESORPTION
DIFFRACTION
ELECTRON DIFFRACTION
ELECTRON SPECTROSCOPY
ELEMENTS
FOILS
FUNCTIONS
HALOGENS
HIGH PRESSURE
HYDROCARBONS
HYDROGEN
HYDROGENATION
HYDROXY COMPOUNDS
LANTHANUM COMPOUNDS
METALS
METHANE
METHANOL
NONMETALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PALLADIUM
PEROVSKITES
PHOSPHORUS
PLATINUM METALS
POLYMERIZATION
POTASSIUM
RARE EARTH COMPOUNDS
SCATTERING
SEMIMETALS
SEPARATION PROCESSES
SILICON
SILICON COMPOUNDS
SILICON OXIDES
SODIUM
SORPTION
SORPTIVE PROPERTIES
SPECTROSCOPY
SULFUR
SURFACE PROPERTIES
SURFACE TREATMENTS
SURFACES
SYNTHESIS
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
ULTRAHIGH VACUUM
WORK FUNCTIONS
X-RAY SPECTROSCOPY