Due to the in situ removal of the inhibitor oxygen using an oxygen transporting membrane, a complete conversion of NO to N(2) was achieved for the first time in a catalytic perovskite membrane reactor.

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A membrane reactor that incorporated hollow fiber in combination with an established catalyst was used for the oxidative coupling of methane (OCM). A perovskite membrane of the composition BaCo x Fe y Zr z O3−δ (BCFZ, x + y + z = 1) allows a controlled oxygen feed into the reactor over its axial length. Using this novel hollow fiber membrane reactor with a 2 wt % Mn/5 wt % Na2WO4 on SiO2 catalyst as a packed bed around the fiber, oxygen separation from air and C2 formation could be established at 800 °C with long-term stability. The highest C2 selectivity of ∼75% was observed at a methane conversion of 6% with a C2H4:C2H6 ratio of 2:1. The highest C2H4:C2H6 ratio of 4:1 and maximum C2 yield of 17% was obtained at 50% C2 selectivity. It is known from the literature that such results can be obtained without a catalyst in a similar membrane reactor only at temperatures 150 °C higher.

A membrane reactor incorporating a hollow fiber with successive parts of oxygen permeable and passivated surface segments has been developed and was used for the oxidative dehydrogenation (DH) of propane. This membrane geometry allows a controlled oxygen feeding into the reactor over its axial length. In the oxidative DH, the thermodynamic limitation of propane DH can be overcome. By using this novel hollow fiber membrane reactor with a Pt/Sn/K DH catalyst, oxygen separation and propene formation could be established even at temperatures as low as 625 degrees C with long-term stability. Combining the hollow fiber membrane and the DH catalyst, the highest propene selectivity of 75% was observed at a propane conversion of 26% and 625 degrees C whereas the best propene yield of 36% was obtained at 675 degrees C (48% propene selectivity). The performance of this reactor is evaluated by applying various reaction conditions