Hydrogen From Acetic Acid As the Model Compound of Bio-Oil Over Ni/Ce-Zr-O Catalyst

The main method available for the hydrogen production from biomass is thermo chemical conversion of biomass to hydrogen, including steam gasification[4, 5] high-pressure supercritical conversion and steam-reforming of bio-oils. Bio-oil is a liquid by fast pyrolysis of biomass, composed by a complex mixture of oxygenated organic molecules and water. Due to its ease of storage and transport, as well as higher energetic density, hydrogen production by steam reforming of bio-oil is recognized as one of the most promising and economical ways to producing hydrogen.

Ni/Ce-Zr-O catalysts were prepared with the different methods of co-precipitation, impregnation and impregnation-co precipitation, and the content of nickel and cerium are 12wt% and 7.5wt%, respectively. Structures and reduction properties as well as surface morphologies of the catalysts were characterized by means of BET�AXRD�AH₂-TPR and SEM.  Results showed that crystal particle size the Ni/Ce-Zr-O catalyst prepared by co- precipitation method was uniformer and pores of that were richer, which made the activity of catalyst for hydrogen production from acetic acid be better than the Ni/Ce-Zr-O catalysts prepared by impregnation method and by impregnation-co precipitation method obviously. When the reaction temperature is 700°C, steam to carbon is 3, and the liquid hourly space velocity is 4.7 h^-1, the hydrogen yield of Ni/ Ce-Zr-O catalyst prepared by co- precipitation method can reach 83.4% of the hydrogen yield from steam reforming of acetic acid.