Solid oxide fuel cells operated by internal partial oxidation reforming of iso-octane

摘要

Two types of solid oxide fuel cells (SOFCs), with thin Ce_(0.85)Sm_(0.15)O_(1.925) (SDC) or 8 mol% Y_2O_3-stabilized ZrO_2 (YSZ) electrolytes, were fabricated and tested with iso-octane/air fuel mixtures. An additional Ru-CeO_2 catalyst layer, placed between the fuel stream and the anode, was needed to obtain a stable output power density without anode coking. Thermodynamic analysis and catalysis experiments showed that H_2 and CO were primary reaction products at ≈ 750℃, but that these decreased and H_2O and CO_2 increased as the operating temperature dropped below ≈600℃. Power densities for YSZ cells were 0.7 W cm~(-2) at 0.7 V and 790℃, and for SDC cells were 0.6 W cm~(-2) at 0.6V and 590℃. Limiting current behavior was observed due to the relatively low (≈20%) H_2 content in the reformed fuel.