Preparation Of Butanol And C₄ Olefins From Ethanol

As important chemical raw materials,butanol and C₄ olefins are widely used in the production of chemical products and pharmaceutical intermediates.The conventional production methods used fossil energy as raw material,with growing concerns about climate change and the depletion of petroleum supplies,the supply of energy tends to diversified,exploration of new clean energy appears more and more urgent.Ethanol is currently produced from renewable resources in large amounts and,in addition to its use is green and clean,holds considerable promise as a building block for the chemical industry,and received extensive attention.Therefore,starting from ethanol,this paper explores the suitable microstructure and chemical state of the catalyst through the regulation and design of catalyst synthesis conditions and reaction conditions,and applies it to ethanol-catalyzed coupling to produce butanol and C₄ olefins.For the reaction of ethanol coupling to butanol,the preparation method and calcination temperature of Mg_x AlO_y catalyst were investigated firstly.The results show that the coprecipitation method and the sample calcined at 600°C have the best performance.When the reaction temperature is 325°C,the selectivity of butanol is 53.68%and the ethanol conversion rate is 29.24%.The treated catalyst is the most stable state and has rich acid-base active sites on the surface.Subsequently,the effect of Co additive on the catalytic performance was investigated.It was found that Co existed on the surface of the catalyst in the form of Co^?+,which promoted the dehydrogenation and the coupling of intermediates on the catalyst surface.The results show that the addition of Co improves the low temperature conversion activity of ethanol and increases the selectivity of C₄-C₁₂OH.When the reaction temperature is 250°C,the conversion rate of ethanol reaches 26.74%,the selectivity of butanol is 59.14%,and the total selectivity of C₄-C₁₂OH higher alcohol is 98.64%,only a small amount of acidic products are formed in the products.For the reaction of ethanol-catalyzed to C₄ olefins,a Co/SiO₂-HAP catalyst with acid-base active sites on the surface was designed.The reaction conditions,Co loading,were investigated.It was determined that when the ratio of Co/SiO₂ to HAP was 1:1,and the reaction temperature was 400°C,the Co loading was 1wt%,the catalyst performance was optimal.Under this condition,Co is highly dispersed on the surface of the catalyst,and the surface of the catalyst has suitable acid-base active sites.Therefore,it has higher catalytic activity,the conversion rate of ethanol is 83.7%,and the selectivity of C₄ olefins is 53.43%.