Dry autothermal reforming of glycerol with in situ hydrogen separation via thermodynamic evaluation

On the basis of the Gibbs free energy minimization principle, the dry autothermal reforming performance of crude glycerol in situ hydrogen separation is investigated via thermodynamic analysis. The impact of hydrogen separation fraction on gas composition in product, carbon formation and reaction heat is studied. It can be found that the hydrogen separation promotes the hydrogen production and hinders methane formation. The hydrogen removal is selective to the reduction of carbon deposition, which improves the carbon formation at a low feed CO₂ to glycerol molar ratio and the impact is reverse for high feed CO₂ to glycerol molar ratio. When the reaction temperature varies from 850 K to 900 K, the required oxygen to glycerol molar ratio of thermal neutral condition is obviously increased from 0.15 to 0.4 with hydrogen removal. Meanwhile, the glycerol impurities evaluation indicates that the syngas yield is significantly reduced with the increase of the glycerol impurities. At a high temperature, the hydrogen removal is in favor of the achievement of autothermal process.