Thermodynamic equilibrium composition analysis of methanol autothermal reforming for proton exchanger membrane fuel cell based on FLUENT Software

Methanol autothermal reforming was thermodynamically analyzed using FLUENT software. The calculation methodology using this software is simple and convenient, and its validity was confirmed by comparing the obtained data with previous studies. As a function of the effects of temperature, pressure, molar steam-to-carbon ratio (S/C), and molar oxygen-to-carbon ratio (O/C) on the objective products, favorable operational parameters were evaluated, under which H2 yield maximizes, the CO molar fraction minimizes and carbon deposition can be eliminated. The equilibrium constants of the possible reactions involved in oxidative methanol steam reforming, coupled with the reaction mechanism for the entire investigated temperature range, were elucidated and discussed. On the basis of the concluded possible mechanisms, three areas are inferred. In each individual area, H2 or CO yield reached a maximum, or solid C was efficiently suppressed. Therein, a favorable operational range is proposed to assure the most optimized product yield.