Synthesis of mesoporous Al_2O_3 macrospheres using the biopolymer chitosan as a template: A novel active catalyst system for CO_2 reforming of methane

摘要

A new and simple method to prepare alumina containing mainly mesopores is described. This alumina has a high surface area (464 m~2/g) and a large pore volume ranging from about 0.35 to 0.65 cm~3/g. The present method was developed using a biopolymer (chitosan) and Al solution. The Al-chitosan solution was added to NH_4OH solution in the form of drops. A hybrid macrosphere compound of aluminum hydroxide and organic polymer is formed. Through polymer elimination by thermal treatment, porous Al_2O_3 spheres with a high specific surface area are obtained. The Ni-impregnated Al_2O_3 spheres showed a high catalytic activity and stability for dry reforming of methane at 650 deg C and a CH_4/CO_2=1 molar ratio.