Steam Reforming of Glycerol for Hydrogen Production over Ni Catalysts Supported by CeO_2-Al_2O_3 Xerogel

摘要

The Ni catalysts supported by CeO_2-Al_2O_3 xerogel were prepared by sol-gel method. The effect of hydrolysis ratio (R at 16.5 and 165) on CeO_2-Al_2O_3 textural properties and phase formation were investigated. The results revealed that the porous texture and the Ni crystalline phase can be controlled by adjusting the hydrolysis ratio. A high surface area and small Ni crystallite size were obtained by using the hydrolysis ratio of 16.5. For hydrogen production via glycerol steam reforming, the Ni catalyst supported on CeO_2-Al_2O_3 xerogel showed a better catalytic performance than that supported on commercial alumina. The promoted Ni catalyst supported on commercial alumina suddenly deactivated after first 12 h, whereas that on Al_2O_3 xerogel performed the catalytic stability more than 20 h. This demonstrated that the catalyst prepared by sol-gel method is an interesting catalyst for using in the glycerol steam reforming because of the catalytic stability enhancement.