Methane conversion in membrane reactors

Mixed-conducting oxygen permeable membrane, Ba_0.5Sr_0.5Co_0.8Fe_0.2O _3-δ, was synthesized by using a combined EDTA-citrate complexing method. The intrinsic catalytic activity of the membrane for CH₄ conversion was investigated. It was found that the membrane had catalytic activity for oxidative coupling of methane and partial oxidation of methane to syngas. The CH₄ conversion rapidly increased two times, the first one was due to the reforming of CH₄ with CO₂; the second one was due to the increase of oxygen permeation rate. Oxygen permeation rate increased with the increase of temperatue. At 850 °C, X (CH₄) = 96%, S(CO)=97.3% and J (O₂) = 11 ml/(cm₂ · min) were obtained. Based on the results of EDS and XRD, carbonates were observed on the reaction side of the membrane surface, but it did not affect the oxygen permeation rate.