Olefin production by a multistep oxidative dehydrogenation in a perovskite hollow-fiber membrane reactor

A multistep permeating hollow-fiber membrane reactor is introduced with successive parts of permeable and passivated surface segments. This geometry allows a controlled oxygen insertion into the reactor over an extended length in order to overcome the equilibrium conversion. At the same time, it provides a lower oxygen concentration, which yields higher ethene selectivity by selectively burning off in situ the hydrogen formed by conventional catalytic dehydrogenation. In the range of low and moderate ethane conversions, this membrane reactor, by using a standard commercial catalyst, can compete with the best catalysts used in the cofeed mode of the oxidative dehydrogenation of ethane (ODE). Reaction conditions with long-term stability could be established that have a comparable ethene yield to those in the industrial steam-cracking process, but at a temperature that is approximately 100 °C lower.