Facile production of higher hydrocarbons from ethane in a catalytic supersonic nozzle

Flowing ethane, typically at 80 Torr, 1000°C, and 10 ms contact time, through a supersonic nozzle made of nickel or molybdenum converts roughly 40% to higher hydrocarbons. In the mass spectra of the products, CnHm, the most prominent peaks contain even numbers of carbon atoms (n = 4, …, 12), but there are also substantial peaks with odd carbon atom numbers (n = 3, …, 11). The largest peaks have m ≈ n hydrogen atoms, but many others also appear. For n = 6 the mass spectrum indicates benzene is probably the sole product, with yield up to 15%. Under the same conditions methane does not form higher hydrocarbons.