Simultaneous production of synthesis gases H2/N2 and H2/CO in a dual-phase mixed conducting membrane reactor

By respectively sending methane and the mixture of air and water to the opposite sides of Ce0.8Sm0.2O2-delta Sr2Fe1.5Mo0.5O5+delta (CSO-SFMO) dual-phase oxygen-permeable membrane reactor, co-production of two synthesis gases H-2/N-2 and H-2/CO were achieved in this work. A porous layer with the same material as the bulk membrane was deposited on the surface of CSO-SFMO membrane to catalyze surface reactions. It was found that CSO with fluorite structure and SFMO with perovskite structure show good chemical compatibility even after being sintered at high temperature. Moreover, the CSO-SFMO dual phase membrane with porous layer exhibits high oxygen permeability and good CO2 tolerance under harsh conditions. Using CSO-SFMO dual phase membrane as reactor, a suitable H-2/N-2 ratio of 3 and H-2/CO ratio of 2 was obtained on the opposite sides of the membrane. Meanwhile, CO selectivity of 98%, CH4 conversion of 97% in the methane side and synthesis gas (H-2 + N-2) production rate of 3.0 cm(3) min(-1) cm(-2) on the feed side were achieved at 900 degrees C.