Research On Methanation Reaction Of Carbon Monoxide

Natural gas can be produced from coal through CO methanation. This method has several advantages such as high calorific value, high conversion rate, high profit and simple process route. As it can be used to produce alternative energy sources of crude oil, this method has attracted more and more reseachers, and it is of strategic significance to study the reaction of CO methanation.In this paper, with the help of BET, XRD, H₂ chemisorption, TPR, TG/DTA, the effects of La₂O₃ and TiO₂ on NiO/Al2O3 catalytic properties were studied. The results showed that the catalytic properties can be significantly improved with the addition of little La. The conversion rate of CO can reach 98% and the selectivity of CH4 reach 96% at 400℃with 3% content of La. After stability test of 264 h, the conversion rate of CO didn't change, while the selectivity slightly decreased a little after 200 h. The addition of TiO₂ also did help in improving the catalytic properties. When the content of TiO₂ is 30%, the conversion rate of CO can reach 100% and the selectivity of CH4 reach 85.5% at 450℃. For La3-Ti30 catalyst with little La, after stability test of 350 h, the conversion rate of CO and the selectivity both kept steady, which were 100% and 98.5% respectively. The results showed that the addition of La₂O₃ and TiO₂ can restrain the NiAl2O4 production, increase the adsorption capacity of H₂ and dispersion of Ni, therefore it can enhance the catalytic activity of CO menthanation.