Effects Of Glucose And Promoter On The Performance Of F-T Synthesis Of Co/SiO₂ Catalyst

Energy is one of the key materials for life and economic progress,and the lifeblood of a country's security and development.The basic characteristics of energy storage in China can be summarized as"rich coal,poor oil and little gas".As an important basic energy and raw material for production,coal plays an important strategic role in the development of China's national economy.However,the use of coal for industrial development is still facing many problems,the most prominent is the environmental problems.In order to solve environmental pollution and effectively accelerate the construction of low-carbon and efficient clean energy security system,Fischer-Tropsch synthesis is an important technology to realize efficient and clean utilization of coal resources.Fischer-Tropsch synthesis is the process of converting CO and H₂into hydrocarbons and other compounds through heterogeneous catalytic reactions.The metals with catalytic activity for the synthesis reaction include nickel,ruthenium,iron and cobalt.At present,the catalysts for industrialization are mainly iron and cobalt based catalysts.Among them,cobalt-based catalysts are characterized by high CO hydrogenation activity at low temperature,high selectivity of heavy hydrocarbons in the products,mainly long-chain hydrocarbons,and low water-gas reactivity.Although the catalysts are easy to be covered by wax in the products and lose their efficacy,their life is still longer than that of iron-based catalysts after regeneration treatment.In this paper,cobalt-based catalyst was prepared by isovolumetric impregnation with SiO₂.The influence of the addition of glucose and different promoters?Pd,Mn,Al?and their contents on the structure and performance of the catalyst was characterized by N₂ low-temperature adsorption,XRD,SEM,H₂-TPR,CO and H₂-TPD.?1?In the process of equivolumetric impregnation,glucose and promoter agent Pd were added separately.After finding the optimal content,cobalt-based F-T synthesis catalyst was prepared by added the both.XRD shows that the addition of glucose can improve the dispersion of catalyst,and TPR shows that the addition of Pd can improve the reducibility of catalyst.The results of the evaluation of the reaction performance of F-T synthesis showed that under the reaction conditions of 230?,2MPa and an flowing speed of 3600 ml/?h·g-cat.?,the CO conversion rate of the catalyst prepared by adding 0.3g glucose and 0.0125%Pd reached 58.1%and the C₅+hydrocarbon selectivity reached 84.1%.?2?The transitionmetal additive Mn is added in the process of equivolumetric impregnation and H₂-TPR showed that Mn could inhibit the reduction of cobalt oxide,and the CO conversion rate of catalyst prepared by adding 0.3g glucose and 3% Mn was 78.4%.However,with the increase of Mn content,the selectivity of C₅+hydrocarbon decreased.?3?The additive Al was added to study the influence of its content on the structure and performance of the catalyst.The CO conversion rate of the catalyst prepared by adding 0.3g glucose and 0.4%Al reached 88.2%and the C₅+hydrocarbon selectivity reached 84.0%.