Mechanisms for the promotion and poisoning of ruthenium catalysts by sulfur

Conference · Sat Mar 01 04:00:00 EST 1986 · Am. Chem. Soc., Div. Pet. Chem., Prepr.; (United States)

OSTI ID:5598516

Kuo, Y J; Cocco, R A; Tatarchuk, B J

Catalytic reactions occurring over ruthenium surfaces can be poisoned or promoted by sulfur depending on both the quantity of sulfur uptake and the specific requirements of the reaction involved. Submonolayers of surface sulfur have been shown to: (i) promote specific rates of hexene isomerization compared to bare metal, (ii) poison hydrogen adsorption sites, (iii) reduce specific rates of hexene hydrogenation, (iv) increase stretching frequencies of adsorbed carbon monoxide molecules in a fashion that depends on crystallite size, and (v) provide greater than 100-fold selectivities towards the hydrodesulfurization versus hydrogenation of thiophene. Alternatively, multi-layer sulfur uptake appears to: (i) promote irreversible hydrogen adsorption, (ii) increase specific rates of thiophene hydrogenation to match that of the HDS pathway and (iii) increase still further specific rates of hexene isomerization compared to bare or surface-sulfided metal. Conversion between the above noted sulfidization regimes, and their corresponding catalytic behaviors, can be achieved through appropriate re-sulfidization and/or annealing procedures. Reaction kinetics, microgravimetry, X-ray photoelectron spectroscopy and pulse oxygen chemisorption confirms this reversible behavior.

• Research Organization: Dept. of Chemical Engineering, Auburn Univ., Auburn, AL
• OSTI ID: 5598516
• Report Number(s): CONF-860425-
• Conference Information: Journal Name: Am. Chem. Soc., Div. Pet. Chem., Prepr.; (United States) Journal Volume: 31:1
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400* -- Petroleum-- Processing
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400104 -- Spectral Procedures-- (-1987)
400201 -- Chemical & Physicochemical Properties
ADSORPTION
ALKENES
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CATALYSTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
CHEMISORPTION
COBALT COMPOUNDS
DEACTIVATION
DESULFURIZATION
ELECTROMAGNETIC RADIATION
ELECTRON SPECTROSCOPY
ELEMENTS
HETEROCYCLIC COMPOUNDS
HEXENES
HYDROCARBONS
HYDROGENATION
IONIZING RADIATIONS
ISOMERIZATION
KINETICS
METALS
MOLYBDENUM COMPOUNDS
NICKEL COMPOUNDS
NONMETALS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHOTOELECTRON SPECTROSCOPY
PLATINUM METALS
PROMOTERS
RADIATIONS
REACTION KINETICS
REFRACTORY METAL COMPOUNDS
RUTHENIUM
SEPARATION PROCESSES
SORPTION
SPECTROSCOPY
SULFIDES
SULFUR
SULFUR COMPOUNDS
THIOPHENE
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
TUNGSTEN COMPOUNDS
X RADIATION
X-RAY SPECTROSCOPY
YIELDS