Oxygenates and Olefins from Alkanes in a Single-Gauze Reactor at Short Contact Times

Partial oxidation of linear C1–C5 alkanes in single-gauze reactors has been examined in the fuel-rich regime at contact times as low as 100 μs. We show that, whereas methane and ethane produce mostly CO and ethylene, respectively, propane, butane, and pentane give high selectivity to oxygenates and olefins. Partial oxidation of propane over a single gauze gives a total selectivity to olefins of nearly 60% with a 2/1 C3H6/C2H4 ratio and minimal oxygenates. Butane oxidation gives a significant amount of oxygenated products, mainly acetaldehyde and formaldehyde with a more open gauze, giving better selectivities. Pentane oxidation gives the highest oxygenate selectivities (up to 60%), the main products being acetaldehyde and propionaldehyde. We argue that this is a coupled heterogeneously initiated homogeneous reaction system, with total combustion primarily catalyzed by the Pt surface and the oxygenates and olefins formed subsequently by gas-phase reactions.