Assessing mixing uniformity in microreactors via in-line spectroscopy  

作　　者：Shusaku Asano Shinji Kudo Taisuke Maki Yosuke Muranaka Kazuhiro Mae Jun-ichiro Hayashi 

机构地区：[1]Institute for Materials Chemistry and Engineering,Kyushu University,Kasuga 816-8580,Japan [2]Department of Chemical Engineering,Graduate School of Engineering,Kyoto University,Japan

出　　处：《Chinese Journal of Chemical Engineering》2024年第2期119-124,共6页中国化学工程学报（英文版）

基　　金：the support of JSPS KAKENHI(21H05083);the Cooperative Research Program of the Network Joint Research Center for Materials and Devices,which was supported by the Ministry of Education,Culture,Sports,Science,and Technology(MEXT),Japan;AUN/SEED-Net(BUU REd-UC 2301)for Research and Education Grant for the University Consortium(consortium name:CES-CHEM)。

摘　　要：Mixing behavior is critical for enhancing the selectivity of fast chemical reactions in microreactors.A high Reynolds number(Re)improves the mixing rate and selectivity of the reactions,but some exceptions of increasing side product yield with the higher Re have been reported.This study investigated the mixing uniformity in microreactors with in-line UV-vis spectroscopy to clarify the relationship between reaction selectivity and chaotic mixing with the higher Re.A colorization experiment of thymolphthalein in an acidic solution was conducted with an excess acid amount to the base to indicate a non-uniformly mixed region.Non-uniformity significantly increased with Re.At the same time,the degree of mixing,which was measured by a usual decolorization experiment,showed that the mixing rate increased with Re.The in-line analysis of the Villermaux-Dushman reaction during the mixing clarified that side product yield significantly increased with Re at around 300 and then decreased at around 1100.These results suggest the compensation effect between the mixing uniformity and mixing rate on the selectivity of the mixing-sensitive reactions.Faster mixing,characterized by a larger Re,can disturb mixing uniformity and,in some cases,decrease reaction selectivity.

关 键 词：MICROREACTOR Villermaux-Dushman reaction In-line analysis MIXING Mass transfer UNIFORMITY 

分 类 号：TQ052[化学工程]