Low temperature methane steam reforming for hydrogen production for fuel cells

Low temperature methane steam reforming to produce H₂ for fuel cells has been calculated thermodynamically considering both heat loss of the reformer and unreacted H₂ in fuel cell stack. According to the thermodynamic equilibrium analysis, it is possible to operate methane steam reforming at low temperatures. A scheme for the low temperature methane steam reforming to produce H₂ for fuel cells by burning both unconverted CH₄ and H₂ to supply the heat for steam methane reforming has been proposed. The calculated value of the heat balance temperature is strongly dependent upon the amount of unreacted H₂ and heat loss of the reformer. If unreacted H₂ increases, less methane is required because unreacted H₂ can be burned to supply the heat. As a consequence, it is suitable to increase the reaction temperature for getting higher CH₄ conversion and more H₂ for fuel cell stack. If heat loss increases from the reformer, it is necessary to supply more heat for the endothermic methane steam reforming reaction from burning unconverted CH₄, resulting in decreasing the reforming temperature. Experimentally, it has been confirmed that low temperature methane steam reforming is possible with stable activity.