Dehydrogenation of propane with selective hydrogen combustion: A mechanistic study by transient analysis of products

The role of lattice and adsorbed oxygen species in propane dehydrogenation in a perovskite hollow fiber membrane reactor containing a Pt-Sn dehydrogenation catalyst was elucidated by transient analysis of products with a sub-millisecond time resolution. Propane is mainly dehydrogenated non-oxidatively to propene and hydrogen over the catalyst, while lattice oxygen of the perovskite oxidizes preferentially hydrogen to water. For achieving high propene selectivity at high propane conversions, the formation of gas phase O-2 on the shell side of the membrane reactor should be avoided. Otherwise, oxygen species adsorbed over the Pt-Sn catalyst participate in non-selective C3H8/C3H6 transformations to C2H4 and COx. (C) 2010 Elsevier B.V. All rights reserved.