Oxidative coupling of methane in a BCFZ perovskite hollow fiber membrane reactor
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 BaCoxFeyZrzO3-delta (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 C-2 formation could be established at 800 degrees C with long-term stability. The highest C-2 selectivity of similar to 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 C-2 yield of 17% was obtained at 50% C-2 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 degrees C higher.