Mechanisms and controlling characteristics of the catalytic oxidation of methane. Technical progress report, June 15, 1990--December 14, 1992

Technical Report · Thu Dec 31 04:00:00 EST 1992

DOI:https://doi.org/10.2172/10108035· OSTI ID:10108035

Klier, K; Simmons, G W; Herman, R G; Miller, A C

We have demonstrated in this work (1) that methane is readily activated at mild conditions (100{degree}C, 1 torr) over a relatively noble metal, Pd. This was observed using a stepped and kinked Pd(679) crystal (1), and other crystal faces are now being investigated to establish whether the cracking of the C-H bond of methane on Pd is structure sensitive or structure insensitive. Oxygen chemisorption is extremely structure sensitive: weakly bonded, highly reactive oxygen overlayers form on Pd(100) surface (2), while strongly bonded, moderately reactive oxygen overlayers form on Pd(111) and Pd(679). Reaction of the weakly bonded oxygen with surface carbide gives rise to CO{sub 2} over clean Pd(100) but to CO over halogen-doped Pd(100) (3--5). The effect of halogens is primarily ensemble-controlling, or oxygen-supply restricting, but long range influence of surface Cl on the strength of the Pd-O bond has also been observed (3). Because the overall chemistry of methane activation with the subsequent oxidation gives rise to the very important oxidative reforming CH{sub 4} + 1/2 O{sub 2} {yields}{sub Pd/Cl} CO + 2 H{sub 2}, Pd/Cl we plan to continue our study of this reaction in detail over Pd(100) (completed), Pd(111) (initiated), Pd(311) (initiated), Pd(110) (to be initiated), and Pd(679) (completed), without and with the halogen modifiers.

• Research Organization: Lehigh Univ., Bethlehem, PA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-86ER13580
• OSTI ID: 10108035
• Report Number(s): DOE/ER/13580--T2; ON: DE93005719
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010408
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201
AIR
C1 PROCESSES
CARBON DIOXIDE
CARBON MONOXIDE
CATALYSTS
CATALYTIC EFFECTS
CHEMICAL ACTIVATION
CHEMICAL AND PHYSICOCHEMICAL PROPERTIES
CHEMICAL BONDS
CLEAVAGE
DOPED MATERIALS
FORMALDEHYDE
HYDROGEN
METHANE
METHANOL
OXIDATION
OXYGEN
PALLADIUM
PARTIAL OXIDATION PROCESSES
PROGRESS REPORT