Hydrogen Production by Steam Reforming of Dimethyl Ether over the Copper Alumina Catalysts: Effect of the Catalysis Activity by the Sol-gel Preparation Methods

摘要

Dimethyl ether (DME) is expected as a clean fuel/energy for the 21st century and hydrogen carrier/storage. I have been studying on DME steam reforming for H_2 production and I have clarified that Cu-Zn/Al_2O_3 catalysts prepared using the sol-gel method are the most effective catalysts for H_2 production. Aiming at improving the catalysis activity for H_2 production, the preparation methods and additive effects have been investigated. The sol-gel methods have been developed. It has been clarified that the consecutive sol-gel method is optimum for preparation of hydrogen production catalyst of DME steam reforming, and that addition of CeO_2 into the Cu-Zn/Al_2O_3 catalysts improves the catalysis activity of methanol steam reforming and DME steam reforming. The stronger acidity of Lewis acid sites works for DME hydrolysis well and well-produced methanol reforms to hydrogen on the copper sites and CeO_2 support. CeO_2 accelerates methanol steam reforming in case of the catalyst prepared using the consecutive sol-gel method. Therefore, copper alumina catalysts prepared using the consecutive sol-gel method produce hydrogen more than copper alumina catalysts prepared using the one-step sol-gel method.