Mechanisms for ethylene hydrogenation and H-D exchange over Pt(111)

Journal Article · Thu Jun 14 04:00:00 EDT 1990 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100375a061· OSTI ID:6330977

Zaera, F ^[1]

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1. Univ. of California, Riverside (USA)

TPD data for C{sub 2}D{sub 4} and C{sub 2}D{sub 3}H chemisorbed over Pt(111) single-crystal surfaces have provided further insight into the mechanisms of ethylene hydrogenation and H-D exchange under ultrahigh vacuum. Desorption of C{sub 2}D{sub 6} from adsorbed C{sub 2}D{sub 4} clearly proves that ethylene undergoes self-hydrogenation by starting with a C-D bond breaking step which provides deuterium atoms to other ethylene molecules. This is the rate-limiting step for both hydrogenation and ethylidyne formation. Coadsorbed hydrogen (or deuterium) increases the ethane yield and lowers the apparent activation energy for that reaction. When H{sub 2} and C{sub 2}D{sub 4} are coadsorbed, hydrogenation and H-D exchange occur simultaneously through the formation of a common intermediate which we believe is an ethyl group.

• OSTI ID: 6330977
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 94:12; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALKENES
CATALYSTS
CHEMICAL REACTIONS
DATA
DATA ANALYSIS
DEUTERIUM
ELEMENTS
ETHYLENE
EXPERIMENTAL DATA
HYDROCARBONS
HYDROGEN ISOTOPES
HYDROGENATION
INFORMATION
ISOTOPES
LIGHT NUCLEI
MEASURING INSTRUMENTS
MEASURING METHODS
METALS
NUCLEI
NUMERICAL DATA
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
PLATINUM
PLATINUM METALS
STABLE ISOTOPES
TRANSITION ELEMENTS