Direct Power Generation from Low Concentration Coal-Bed Gas by a Catalyst-Modified Solid Oxide Fuel Cell

Clear utilization of low-concentration coal-bed gas (LC-CBG) would save energy, mitigate greenhouse gas emissions, and reduce explosion accidents during a coal-mining process. In this paper, a novel catalyst Ni/BaO/CeO₂ (NBC) is developed for CH₄ partial oxidation and is used as an independent catalyst layer of a Ni cermet anode. LC-CBG with composition of 30 % methane and 70 % air is directly fed to the catalyst-modified SOFC to generate electricity. Operated on 30 % LC-CBG, the NBC-modified cell shows better performance and discharge stability than the conventional cell without the catalyst layer. Gas chromatography (GC) analysis on effluent gases extracted from the operating catalyst-modified cells also indicates a higher CH₄ conversion when the cell is fed with 30 % LC-CBG than when fed with 3 % H₂O-humidified methane. Post-mortem microstructures of cell surface were analyzed. The NBC-modified cell has a potential application for fuels containing low concentration methane and air.