Simultaneous generation of synthesis gas and electric power by internal reforming fuel cells utilizing LaGaO3 based electrolytes

A novel solid oxide fuel cell (SOFC) utilizing partial oxidation of methane (CH4 + 1/2O(2) = CO + 2H(2)) as internal reforming reaction was investigat ed in the present study. Large electric power as well as CO-H-2 mixture wit h molar ratio of 2 were obtained by applying LaGaO3 perovskite as electroly te. Although the open circuit potential decreased, the maximum power densit y increased by doping a small amount of Co to the LaGaO3 electrolyte. In pa rticular, the increase in the power density at 1073 K was significant. Incr easing the amount of doped Co monotonically enhanced the hole conduction re sulting in a decrease in the open circuit potential and an increase on the amount of leaked oxygen which results in diminished electric power. Consequ ently, it became clear that the optimized composition for this electrolyte was La0.9Sr0.1Ga0.8Mg0.115Co0.085O3 considering the power density and the a mount of oxygen leakage. Although the thickness of electrolyte with the abo ve composition was as thick as 0.5 mm, a maximum power density and yield of synthesis gas were obtained at 242 mW/cm(2) and 16%, respectively at 1073 K. (C) 1998 Published by Elsevier Science B.V. All rights reserved.