REACTIONS BETWEEN HYDROCARBONS AND DEUTERIUM ON CHROMIUM OXIDE GEL. III. ISOTOPIC EXCHANGE BETWEEN DEUTERIUM AND CYCLOALKANES

Journal Article · Tue Dec 20 04:00:00 EST 1960 · Journal of the American Chemical Society (U.S.)

DOI:https://doi.org/10.1021/ja01509a021· OSTI ID:4115590

Stoddart, C T.H.; Pass, G; Burwell, Jr, R L

The investigation of isotopic exchange on a chromia catalyst between deuterium and these various hydrocarbons are reported: the cycloalkanes, cyclopropane to cyclooctane, methane, ethane, hexane, and 2.3-dimethylbutane. At 2O0 deg C, the rates of exchange relative to cyclohexane are: cyclopropane, 50; ethylcyclobutane and cyclooctane, 5; ethane, 0.13. The others fall in the range, 1 to 3, except for methane which is about twice ethane. The activation energies of exchange of cyclopropane and of ethane are 7 and 21 kcal. Cyclopropane exchange can be detected even at 25 deg C, and, at 100 deg C, ring opening with an activation energy of 12 kcal becomes detectable. The exchange patterns of ethane, 3.3-dimethylpentane, and cyclopropane very closely follow the random distribution characteristic of a process which introduces but one deuterium atom per adsorption step. For the others, at about 2OO deg C, 95 to 99% of the exchanged molecules follow such a pattern. A few per cent follow a pattern involving extensive multiple exchange, and with cycloalkanes, a few per cent appear as excess cycloalkane-d/sub 2/ and -d/sub 3/. (auth)

• Research Organization: Northwestern Univ., Evanston, Ill.
• Sponsoring Organization: USDOE
• NSA Number: NSA-15-007257
• OSTI ID: 4115590
• Journal Information: Journal of the American Chemical Society (U.S.), Journal Name: Journal of the American Chemical Society (U.S.) Vol. Vol: 82; ISSN JACSA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ACTIVATION ENERGY
ADSORPTION
ALKANES
BUTANE
CATALYSIS
CHEMICAL REACTIONS
CHEMISTRY
CHROMIUM OXIDES
COLLOIDS
CYCLOALKANES
DETECTION
DEUTERIUM
ETHANE
ETHYL RADICALS
HEXANE
HYDROCARBONS
ISOTOPIC EXCHANGE
METHANE
METHYL RADICALS
MOLECULES
OCTANE
PENTANE
PROPANE