Innovative steam methane reforming for coproducing CO-free hydrogen and syngas in proton conducting membrane reactor

Steam methane reforming (SMR) is a commercial process to produce syngas. Normally, the as-produced syngas is characterized by a H-2/CO ratio of 3. However, such H-2/CO ratio is unsuitable for Fischer-Tropsch synthesis. The hydrogen obtained by subsequent upgrading of syngas usually contains residual CO, which readily deactivates Pt electrocatalysts in fuel cells. Here we report an innovative route by coupling SMR with H-2 removal in a proton conducting membrane reactor to coproduce syngas with a preferable H-2/CO ratio of 2 and CO-free H-2 on opposite sides of the membrane, which can be directly used for Fischer-Tropsch synthesis and fuel cells, respectively. Notably, H-2 is in-situ extracted by the membrane that only allows the permeation of H-2 as protons through the oxide lattice with infinite selectivity, and thus the obtained H-2 is CO-free. This work could provide an alternative option in one-step conversion of methane into two inherently separated valuable chemicals.