Hydrogen production by glycerol steam reforming with Pt/SiO2 and Ni/SiO2 catalysts

Pt and Ni catalysts supported on SiO2 were prepared with different metal content in order to apply them in steam reforming of glycerol at temperatures between 350 °C and 450 °C. Conditions of temperature and space time (τ) that can provide the total conversion of glycerol to gaseous products were found. Based on the identification of liquids or reaction intermediates, we found that Ni and Pt have the same reaction steps. Thus, a schematic representation of reaction pathways was proposed involving successive steps of dehydrogenation and C–C bond cleavage, leading to H2 and CO. The different levels of conversion, selectivity and stability of catalysts were analyzed. Pt catalysts were more active and stable than Ni catalysts. Ni catalysts showed differences in the selectivity to gaseous products due to the increased contribution of the WGS reaction. The Pt catalysts have shown a total conversion to gaseous products at 450 °C, without deactivation during the 40 reaction hours.