Biogas Catalytic Reforming Studies on Nickel-Based Solid Oxide Fuel Cell Anodes

详细信息    查看全文

• 作者：G. B. Johnson ; P. Hjalmarsson ; K. Norrman ; U. S. Ozkan and A. Hagen
• 关键词：Biogas Reforming ; Catalyst Deactivation ; CH4 Dissociation ; CO2 Dissociation ; Ni/ScYSZ SOFC Anode ; Ni/YSZ ; Pd-CGO ; Solid Oxide Fuel Cell ; Sulfur Poisoning ; Temperature-Programmed Reactions
• 刊名：Fuel Cells
• 出版年：2016
• 出版时间：April, 2016
• 年：2016
• 卷：16
• 期：2
• 页码：219-234
• 全文大小：1837K
• ISSN：1615-6854

文摘

Heterogeneous catalysis studies were conducted on two crushed solid oxide fuel cell (SOFC) anodes in fixed-bed reactors. The baseline anode was Ni/ScYSZ (Ni/scandia and yttria stabilized zirconia), the other was Ni/ScYSZ modified with Pd/doped ceria (Ni/ScYSZ/Pd-CGO). Three main types of experiments were performed to study catalytic activity and effect of sulfur poisoning: (i) CH₄ and CO₂ dissociation; (ii) biogas (60% CH₄ and 40% CO₂) temperature-programmed reactions (TPRxn); and (iii) steady-state biogas reforming reactions followed by postmortem catalyst characterization by temperature-programmed oxidation and time-of-flight secondary ion mass spectrometry. Results showed that Ni/ScYSZ/Pd-CGO was more active for catalytic dissociation of CH₄ at 750 °C and subsequent reactivity of deposited carbonaceous species. Sulfur deactivated most catalytic reactions except CO₂ dissociation at 750 °C. The presence of Pd-CGO helped to mitigate sulfur deactivation effect; e.g. lowering the onset temperature (up to 190 °C) for CH₄ conversion during temperature-programmed reactions. Both Ni/ScYSZ and Ni/ScYSZ/Pd-CGO anode catalysts were more active for dry reforming of biogas than they were for steam reforming. Deactivation of reforming activity by sulfur was much more severe under steam reforming conditions than dry reforming; a result of greater sulfur retention on the catalyst surface during steam reforming.