Synthesis Of Ethyl Acetate Catalyst In Ethanol Dehydrogenation

Zr(OH)₄ gel was prepared by sol-gel method from ZrOCl2 material. Then the the gel was alcoholized by ethanol, dried, and calclined to get ZrO₂ nanometer scale particles. Supported catalysts CuO/ZrO₂ were prepared by impregnation method. Doped CuO-ZrO₂ catalysts were prepared that Cu(NO₃)2 was supported on Zr(OH)₄. CuO·ZrO₂ catalysts were prepared by co-precipitated method. The catalyst Pd-CuO?ZrO₂ was prepared that PdCl2 was supported on Cu(OH)2-Zr(OH)₄. The catalysts were characterized by XRD,N2 adsorption-desorption,TG-DCS,TEM,SEM and Raman. Catalytic activities of the catalysts were investigated by dehydrogenation of ethanol to ethyl acetate as the probe reaction.The result of research show that ZrO₂ which has higher surface area and pore volum,well-distributed pore is got; CuO·ZrO₂ catalysts has the highest surface area and pore volum during the samples prepared by different ways; That the active constituent Cu was added into CuO-ZrO₂ and CuO?·ZrO₂ can put off the transition of ZrO₂ from tetragonal crystal to monoclinic crystal and the delay of transition in doped CuO-ZrO₂ catalysts is more evidence; The addition of Pd and Cu can change the crystal structure more than only Cu by increasing its content.Catalytic activities of the catalysts were investigated. The results indicate that the catalysts prepared by different ways have the catalytic activity by dehydrogenation of ethanol to ethyl acetate, the active constituent Cu can improve the selectivity of ethyl acetate. The influence of activity by different metal, reaction temperature, velocity of flow, temperature of calcination, content of metal and different methods of preparation was studied. The discipline of catalytic activity is: CuO?ZrO₂>CuO-ZrO₂>CuO/ZrO₂. The process conditions were optimized as following: the content of Cu is 6%, the temperature of calcinations is 550℃, the reaction temperature is 473 K, the space velocity is 30 mL/min. The catalytic activity of CuO-ZrO₂ is between the CuO·ZrO₂ and CuO/ZrO₂, the conversion of ethanol is 28% and the selectivity of ethanol to ethyl acetate is 83% is attained. The CuO?ZrO₂ catalyst has the highest catalytic activity during the catalysts. The conversion of ethanol is 39% and the selectivity of ethanol to ethyl acetate is 88%. The results of stability tests indicated that the catalysts performed a well performance. The research of Pd-CuO?ZrO2 activity shows that the addition of Pd can increase the conversion of ethanol, but it is not good for the selectivity of ethanol to ethyl acetate.