微反应器内氧化锌诱导的ZIF-8膜制备及其催化性能

Preparation of ZIF-8 films in a microreactor and their catalytic performances

针对微通道内存在的催化多孔载体层或催化剂层制备及固载难点技术问题,基于石英毛细管微通道反应器管径小而长径比大、表面惰性的特点,利用新型金属有机骨架(MOFs)ZIF-8材料拥有的巨大比表面积、良好热稳定性和催化性质,采用生长ZnO修饰层诱导的流动合成方法在毛细石英管微通道内制备了ZIF-8膜,研究了流动合成时间与生长形成ZIF-8膜厚度的关系。构建的ZIF-8膜微反应器应用于催化苯甲醛与氰基乙酸乙酯的Knoevenagel缩合反应,并考察了反应条件对反应性能的影响和ZIF-8催化膜层的催化稳定性。在温和条件下可获得收率近100%的目标产物,并表现出良好的反应操作稳定性。

For the technical problems of preparation and immobilization for porous support layer and catalyst layer in microchannels, based on characteristics of small diameter and large aspect ratio, inert surface for capillary mieroehannel reactor and the huge surface area, good thermal stability, catalytic properties of novel metal-organic frameworks （MOFs） ZIF-8 material, a ZIF- 8 film in a quarts capillary was prepared by ZnO modification layer-induced flow synthesis method. The relationship between the ZIF-8 film thickness and the synthetic growth time was investigated. This ZIF-8 film microreactor was applied in the Knoevenagel condensation of benzaldehyde （BA） and ethyl cyanoacetate （ECA） for testing its catalytic performance. Nearly 100% product yield could be achieved under optimized wild reaction condition. And also the ZIF-8 film microreactor could demonstrate excellent catalytic stability.