Non-noble metal catalysts coated on oxygen-permeable membrane reactors for hydrogen separation

Catalytic membrane reactors for hydrogen separation based on oxygen-permeable membranes have attracted much attention. It is of great significance to develop effective non-noble metal catalysts for the membrane reactor. Fe, Co and Ni based catalysts are good alternatives due to their high abundance and low cost in practical applications. In this work, M/SDC (M = Fe, Co and Ni) catalysts are prepared for hydrogen separation. It was demonstrated that the catalytic activity increases in the order of Co/SDC < Fe/SDC < Ni/SDC. The hydrogen separation rate of the membrane reactor with the Ni/SDC catalyst is 1.5 times higher than that of with the Co/SDC catalyst under the same conditions. A model was used to estimate the resistances of surface reaction and bulk diffusion. It is concluded that the hydrogen separation process is jointly controlled by surface reactions and bulk diffusion even for the membrane reactors with the Ni/SDC catalyst.