Simultaneous overcome of the equilibrium limitations in BSCF oxygen-permeable membrane reactors: Water splitting and methane coupling

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• 作者：Zhengwen Cao ; Heqing Jiang ; Huixia Luo ; Stefan Baumann ; Wilhelm A. Meulenberg ; Hartwig Voss ; J¨¹rgen Caro
• 关键词：Water splitting ; Methane coupling ; Equilibrium limitation ; Oxygen permeable membrane ; Perovskite
• 刊名：Catalysis Today
• 出版年：2012
• 出版时间：15 October, 2012
• 年：2012
• 卷：193
• 期：1
• 页码：2-7
• 全文大小：921 K

文摘

The equilibrium limitations of water splitting and the coupling of methane to C₂ hydrocarbons (ethane + ethylene) were simultaneously overcome by using a perovskite Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3?¦Ä (BSCF) oxygen-permeable membrane reactor. Oxygen produced from thermal water splitting was transported through the BSCF membrane and consumed in the coupling of methane. The BSCF membrane consists of an about 70 ¦Ìm thick dense BSCF layer on an about 0.8 mm thick porous BSCF layer as support. By applying the membrane reactor concept instead of a fixed bed reactor without oxygen supply, the methane conversion and C₂ yield increased from 3.7 % to 26 % and 3.1 % to 6.5 % at 950 ¡ãC, respectively. In both experiments, the supported 2 wt. % Mn-5 wt. % Na₂WO₄ catalyst was used at 950 ¡ãC. Simultaneously, about 9 % of the H₂O injected was converted to hydrogen with a production rate of about 3.3 cm³ min^?1 cm^?2 at 950 ¡ãC which is higher than 1 m³ (STP) H₂ m^?2 h^?1.