Low Temperature Synthesis of Mesoporous γ-Alumina supported Nickel Oxides and their Catalytic Application for CO2 Methanation

The mesoporous gamma-alumina supported nickel oxides with different Ni/Al molar ratios (x = 0.05, 0.10, 0.125, 0.25, 0.50) have been prepared by a simple partial hydrolysis of aqueous solution of Al(NO3)(3) and Ni(NO3)(2) with (NH4)(2)CO3 without templates or organic surfactants at low calcination temperature of 400 degrees C. The as-prepared materials possessed wormhole-like mesoporous structures with large specific surface areas of 252-477 m(2)/g and narrow pore size distributions in the range of 3-4 nm. The specific surface areas and pore volumes of the materials gradually decreased with the increase in the Ni/Al molar ratio and the nickel species were highly dispersed in the materials. Among the catalysts tested for the methanation of CO2, the mesoporous gamma-alumina supported nickel oxides with the Ni/Al molar ratios of 0.25 revealed the best catalytic performance and showed the similar catalyst activity to the counterpart with ordered mesoporous alumina supported nickel oxide synthesized through templating approach.