不同载体对Cu系催化剂催化醋酸异丙酯加氢工艺的影响  

Effects of supports of Cu-based catalysts on hydrogenation of isopropyl acetate to alcohols

作　　者：杨恒东[1] 李有林[1] 崔咪芬[1] 费兆阳[1,2] 陈献[1] 汤吉海[1] 乔旭[1,2] 

机构地区：[1]南京工业大学化工学院,江苏南京210009 [2]南京工业大学材料化学工程国家重点实验室,江苏南京210009

出　　处：《南京工业大学学报（自然科学版）》2016年第2期100-106,共7页Journal of Nanjing Tech University(Natural Science Edition)

摘　　要：本文以醋酸异丙酯为原料催化加氢,同时制备乙醇和异丙醇。用共沉淀法制备SiO_2、Al_2O_3、ZrO_2和TiO_24种不同载体负载的Cu系催化剂,分别考察它们的催化反应性能;借助N2吸附-脱附仪、X线衍射仪(XRD)、H_2程序升温还原(H_2-TPR)、N_2O氧化滴定及NH3程序升温脱附(NH_3-TPD)等表征手段,分析对比4种载体对Cu的分散性、CuO-载体之间的协同作用、表面酸性等的影响及最终对反应结果的影响。结果表明:Cu/SiO_2表现出较好的催化活性且主产物的选择性最高;Cu/ZrO_2中因CuO与ZrO_2间的协同作用促进了Cu的高度分散,因而活性最高,但较强的酸性降低了主产物乙醇的选择性;Cu/TiO_2和Cu/Al_2O_3的催化活性以及主产物选择性都明显偏低。在Cu/SiO_2催化剂上进行了醋酸异丙酯加氢反应的工艺优化,筛选出了最佳工艺条件:温度290℃,反应压力6 MPa,氢酯进料摩尔比30,质量空时96 g·h/mol。在最佳条件下,醋酸异丙酯的转化率达96%,乙醇的选择性达94%,异丙醇的选择性达95%。Ethanol and isopropanol were prepared from the hydrogenation of isopropyl acetate on copperbased catalysts with different supports（ SiO_2,Al2O3,ZrO_2,TiO_2） prepared by ammonia co-precipitation method. The catalytic performances and properties were characterized by N2adsorption-desorption,X-ray diffraction（ XRD）,H_2 temperature programmed reduction（ H_2-TPR）,N_2O oxidation titration,and NH_3 temperature programmed desorption（ NH3-TPD）. The effects of different supports on copper dispersion,the synergy between CuO-carrier,surface acidity, and the ultimate effects on the reaction were investigated. Results showed that Cu / SiO_2 catalyst exhibited the highest selectivity to the ethanol and theisopropanol,and higher catalytic activity; Cu / ZrO_2 exhibited the best catalytic activity due to the synergy between CuO and ZrO_2,thus promoting the high dispersion of Cu,while the strong acid resulted in the reduction of ethanol selectivity; Cu / TiO_2 and Cu / Al2O3 exhibited the lower activity and selectivity to the ethanol and the isopropanol. The suitable process conditions were obtained on Cu / SiO_2 catalyst 290 ℃,the pressure of 6. 0 MPa,the molar ratio of hydrogen and isopropyl acetate of 30,and the space-time based on the catalyst mass of 96 g · h / mol. Under these conditions,the conversion of isopropyl acetate was96%,the selectivities of ethanol and isopropanol were 94% and 95%,respectively.

关 键 词：载体 Cu系催化剂 醋酸异丙酯 加氢 乙醇 异丙醇 

分 类 号：TQ032.4[化学工程]