Study Of Catalysts In Hydrogenation Of Ethyl Acetate To Ethanol

Hydrogenation of ethyl acetate has been proposed for a new way in manufacturing the ethanol while the key is the catalysts and process conditions. In this thesis, the copper-based catalyst is studied. Two series of catalysts were prepared with different catalyst components, other catalysts were prepared using four different preparation methods, and all of them have high activity for the hydrogenation of ethyl acetate to ethanol. In the fixed-bed micro-reactor for catalytic reaction, the catalyst supporter, active ingredients, preparation conditions and reaction conditions, such as calcination temperature, reduction temperature, reaction temperature and molar ratio of Cu/Zn, were optimized screening to make the catalyst reaches the highest activity and obtain the desired product. The catalysts are characterized by XRD, H2-TPR, TGA, TEM and XPS. The experimental results show that, the Cu-Zn-Al catalysts prepared by impregnation and Cu-Zn-Si catalysts prepared by co-precipitation have very high activity in hydrogenation of ethyl acetate to ethanol. The ethyl acetate conversion is above65%, and the selectivity of ethanol in more than90%. The Cu-Zn-Si catalysts prepared by co-precipitation using sodium silicate as the precipitation that was calcined under200℃for5hours, when the reduction temperature, reaction temperature, reaction pressure and mass space velocity were300℃,250℃,2MPa and2h-1, the conversion can reach81.6%. Zn as the modified metal added in copper catalysts can increase the catalytic activity of the active metal Cu. The added Zn made mesoporous characteristics more obviously while increasing the pore size of the catalyst and the dispersion of Cu, reducing specific surface area and the size of Cu metal particles, thus greatly improved the catalytic activity. The study found that different preparation methods had a great influence on the catalytic activity. The preparation method can affect the dispersion and the size of the active Cu, and further influenced the activity of the catalyst. In the conditions that calcination temperature, reaction temperature and reaction pressure were500℃,250℃and2MPa. catalysts prepared by co-precipitation had the highest activity in hydrogenation of ethyl acetate, so the co-precipitation was the best method in preparation of ethyl acetate hydrogenation catalyst.