Oxidation of C2 hydrocarbon products during the oxidative coupling of

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J . Phys. Chem. 1990, 94, 3756-3761

Oxidation of C, Hydrocarbon Products during the Oxidative Coupling of Methane over a Li/MgO Catalyst Peter F. Nelson* CSIRO Division of Coal Technology, P.O. Box 136, North Ryde 2113, Australia

and Noel W. Cant School of Chemistry, Macquarie University, Sydney, NS W 2109. Australia (Received: August 21, 1989)

The contribution of oxidation of C2 hydrocarbons to carbon oxide formation during the oxidative coupling of methane over a Li/MgO catalyst has been investigated. Small quantities of 13C2H6and I3C2H4were added to CH4/02 in a recycle reactor and the I2C and 13C contents of C2H6, C2H4, CO, and C 0 2 were determined by mass spectrometry and Fourier transform infrared spectroscopy. At temperatures greater than 740 "C, C2 oxidation was responsible for the formation of 30-80% of the carbon oxides. However at lower temperatures (