丁酮和甲醛羟醛缩合与催化加氢制备甲基异丙基酮的研究  

Preparation of methyl isopropyl ketone from methyl ethyl ketone and formaldehyde via aldol condensation and sequential catalytic hydrogenation

作　　者：汪波 孙培永[1] 张胜红[1] 姚志龙[1] WANG Bo;SUN Pei-yong;ZHANG Sheng-hong;YAO Zhi-long(Beijing Key Laboratory of Enze Biomass Fine Chemicals,College of New Materials and Chemical Engineering,Beijing Institute of Petrochemical Technology,Beijing 102617,China)

机构地区：[1]北京石油化工学院新材料与化工学院,恩泽生物质精细化工北京市重点实验室,北京102617

出　　处：《现代化工》2023年第5期121-126,共6页Modern Chemical Industry

基　　金：北京市教育委员会科技计划项目(KM201910017010)。

摘　　要：以Al_(2)O_(3)为载体,采用等体积浸渍法制备了Ni/Al_(2)O_(3),利用XRD、N_(2)物理吸附、H_(2)-TPR和NH3-TPD对Ni/Al_(2)O_(3)进行表征,并考察了其催化丁酮和甲醛羟醛缩合(aldol)反应产物脱水加氢制备甲基异丙基酮(MIPK)的反应性能。结果表明,在醛酮摩尔比为1.1、反应温度为50℃和反应时间为4 h的条件下,5%三乙胺催化丁酮和甲醛交叉aldol反应的转化率为61.5%,目标产物选择性超过90%;以此反应液为原料,Ni/Al_(2)O_(3)在240℃、0.1 MPa H_(2)和0.5 h-1空速条件下能够实现80%的MIPK选择性和50%的MIPK收率。此外,Ni/Al_(2)O_(3)催化剂具有较高的结构稳定性,在脱水加氢反应中未出现明显的Ni粒子聚集。丁酮和甲醛羟醛缩合和催化加氢串联反应制备MIPK遵循平行-序列的反应路径,且产物选择性主要取决于丁酮和甲醛的定向aldol反应。Ni/Al_(2)O_(3)catalysts are prepared via an incipient wetness impregnation method with Al_(2)O_(3)as carrier,and characterized by means of XRD,N_(2)physical adsorption,H_(2)-TPR,and NH 3-TPD.The performance of Ni/Al_(2)O_(3)catalysts is evaluated in catalyzing the production of methyl isopropyl ketone(MIPK)through hydrogenation of the products from aldol condensation reaction between methyl ethyl ketone(MEK)and formaldehyde.It is shown that the conversion of MEK reaches 61.5%and an overall selectivity of the desired aldol products exceeds 90%when 5%trimethylamine is served as catalyst,the molar ratio between formaldehyde and MEK is 1.1,temperature is 50℃,and the reaction lasts for 4 h.With the aldol products as feeding materials,the selectivity and yield of MIPK can realize 80%and 50%,respectively when Ni/Al_(2)O_(3)catalysts are used at 240℃,0.1 MPa H_(2),and a space velocity of 0.5 h-1.Besides,Ni/Al_(2)O_(3)catalysts are stable in the hydrogenation reaction without observable aggregation of Ni particles during a period of 80 h.It is indicated that the overall tandem reaction proceeds via a combination of parallel and consecutive steps,and the selectivity of MIPK relies mainly on the crossed aldol reaction between MEK and formaldehyde.

关 键 词：丁酮 甲醛 羟醛缩合反应 催化加氢 甲基异丙基酮 

分 类 号：TQ032[化学工程]