操作条件对固体氧化物燃料电池阳极反应转变的影响

研究了不同电流密度下,甲烷浓度、反应温度对甲烷在SOFC中反应由部分氧化到完全氧化转变的规律;测量了不同电流密度下,阳极出口气体产生速率;确定了甲烷浓度和电池反应温度变化时甲烷电化学反应由部分氧化转变为完全氧化的电流密度门槛值,及该门槛值与甲烷浓度、电池操作温度的变化关系.结果说明甲烷开始发生完全氧化的电流密度门槛值与甲烷浓度成正比;甲烷浓度一定,温度升高,甲烷开始发生完全氧化的电流密度的门槛值也随之提高.

Effect of operation conditions on reaction over anode in SOFC

The reactions of low and medium concentration dry methane over the anode of solid oxide fuel cell (SOFC) with Ni/yttria-stabilized zirconia(YSZ) anode and YSZ electrolyte were studied. The production rates of gases at anode outlet were measured at different current densities. Mass balance and the relations of production rates with reaction rates were used to analyze the chemical and electrochemical reactions taking place in parallel. For low concentration dry methane,partial oxidation of methane occurred at a low current density,electrochemical oxidations of hydrogen and carbon monoxide took place with the increasing current density. For medium concentration methane,only partial oxidation of methane occurred. Carbon deposition was found in all the tests.