微通道反应器内“就地”合成沸石膜催化层及其性能

Preparation and Catalytic Performance of Zeolite Layer in Microchannels of a Microreactor by an on-Site Flow Synthesis Method

采用简单、新颖的沸石粒子引入方法,将NaX沸石晶种引入不锈钢微反应器的微通道内,并用流动法"就地"直接在微通道内通过沸石生长形成NaX沸石膜层,经铯离子交换处理成为CsNaX催化层,用苯甲醛和氰基乙酸乙酯的Knoevenagel缩合反应评价了该催化层的催化性能.结果表明,微通道内形成的沸石膜层连续,均匀,具有良好的催化功能.微反应器内缩合反应的结果明显优于传统反应器.

A zeolite-based microreactor was fabricated and tested for Knoevenagel condensation oetween benzaldehyde and ethylcyanoacetate with a continuous CsNaX zeolite layer as the catalyst, which was prepared within the microreactor channel using a novel flow method. The method involved two-step procedures in which NaX zeolite seeds for the growth of zeolite layer were introduced onto the internal surface of the microchannel by using a seeding technique and then grew into a zeolite layer by an on-site flow hydrothermal treatment followed by ion-exchange with 0.5 mol/L CsNO3 solution. The zeolite-based microreactor showed higher catalytic activity for the reaction compared with the conventional batch reactor.