Hydrogen production from steam reforming of ethylene glycol over supported nickel catalysts

A series of nickel catalysts were prepared by the impregnation and co-precipitation methods and characterized by X-ray diffraction, nitrogen physisorption, and H₂ temperature-programmed reduction. The effects of nickel loading, calcination temperature, reaction temperature, support modification and cobalt oxide addition on the catalytic activity and selectivity to H₂ in the steam reforming of ethylene glycol were investigated. The results indicate that the nickel catalyst prepared by co-precipitation has smaller particle size and relatively higher activity in comparison with the catalyst prepared by impregnation. Adding a small amount of cobalt oxide to the Ni/CeO₂ catalysts can enhance the catalytic activity; over the Ni-Co bimetallic catalyst, the yield of hydrogen reaches 72.6%. Modifying CeO₂ with Al₂O₃, TiO₂ and ZrO₂ also has a certain influence on the catalytic activity and the Ni/CeO₂-Al₂O₃ catalyst exhibits the highest activity, with an ethylene glycol conversion of 94% to gaseous products and a hydrogen yield of 67.0%. However, Ni/CeO₂-SiO₂ shows a very low activity in spite of its large surface area and pore volume.