tailieunhanh - A study on methanation of carbon monoxide over catalysts NiO/TiO2 and NiO/γ-Al2O3

The catalyst NiO/TiO2 and seven samples of NiO/γ-Al2O3 with NiO content from to 60% have been obtained and studied. Physico-chemical characteristics of the catalysts were determined by methods of Adsorption (BET), X-ray Diffraction (XRD), TemperatureProgrammed Reduction (TPR) and Hydrogen Pulse Titration. The catalytic properties of the obtained samples were investigated in the reaction of CO methanation at temperatures 180 – 220◦C and mole ratios hydrogen/carbon monoxide 25-100. It has been found that the optimal regime for catalyst treatment is calcination at 600◦C and reduction at 400◦C. The catalyst NiO/TiO2 expressed very high activity but in case of NiO/Al2O3 for having high activity it was necessary to raise the content of NiO up to . This catalyst has been indicated to be the most active in all the studied conditions. The determining factors for expressing high activity in the catalyst NiO/TiO2 are the presence of spinel NiTiO3 and the optimal average size of nickel assemblies but in the catalyst NiO/Al2O3 – the optimal size of active centers, big values of specific surface area and content of NiO and the high thermal stability. | A study on methanation of carbon monoxide over catalysts NiO TiO2 and NiO γ-Al2O3