Partial oxidation of methane to syngas in a mixed-conducting oxygen permeable membrane reactor

Mixed-conducting oxygen permeable membranes represent a class of novel ceramic membranes, which exhibit mixed oxygen ionic and electronic conductivities. At high temperatures, oxygen can permeate through the membrane from the high to low oxygen pressure side under an oxygen concentration gradient. Theoretically, the permselectivity of oxygen is 100%. Recently, a novel mixed-conducting membrane - Ba_0.5Sr_0.5Co_0.8Fe_0.20O _3-δ has been developed, which shows extremely high oxygen permeability and promising stability. Furthermore, the reactor made with such membranes was successfully applied to the partial oxidation of methane to syngas reaction using air as the oxygen source, which realized the coupling of the separation of oxygen from air and the partial oxidation of membrane reaction in one process. At 850°C, methane conversion > 88%, CO selectivity >97% and oxygen permeation rate of about 7.8 mL/(cm² · min) were obtained.