Abstract

Microreaction technology have evolved rapidly over the last two decades from early devices and concepts to encompass a wide range of commercial equipment and applications. This technology has also been more and more adopted by the chemistry community with the term of ‘flow chemistry’. The objective of my work is to develop the microreaction systems to investigate the reaction kinetics and mechanisms which are difficult or toilsome to performed in conventional batch reactors and further realize the process intensification. Also, my work aims to develop new synthetic path and efficient tools for chemical synthesis.

The first part studied the kinetics and mechanisms of Beckmann rearrangement of cyclohexanone oxime (fast and strongly exothermic reaction) and then developed a new microsystem to intensify the process. The new system is successful in reducing the residence time and side products even without heat exchanger.

The second part was developing a new organocatalyst for Beckmann rearrangement without producing ammonium sulfate based on  trifluoroacetic acid. High selectivity (99+%) and faster reaction rate were achieved. A novel one-step synthesis from cyclohexanone to caprolactam was proposed.

The third part focused on the hydrogenation. The flow dynamics, gas-liquid mass transfer of gas-liquid flow in micro-packed beds were studied. A novel microsystem for hydrogenation kinetics measurement was developed aiming to realize fast catalyst screening and kinetics study . In addition, a simple, fast and general method to measure the gas solubility, gas diffusivity in liquids and fast gas-liquid reactions kinetics was developed.

Biography:

Jisong Zhang received his B.S. (2009) and PhD (2014) in Chemical Engineering from Tsinghua University, China. He was a postdoc in the same group from 2014 to 2015 under the supervision of Prof. Guangsheng Luo. From 2015 until now, he moved to Department of Chemical Engineering, Massachusetts Institute of Technology and worked in Prof. Klavs Jensen’s group as a postdoctoral associate. Dr. Zhang’s research interests focus on micro-reaction technology, organocatalysis and flow chemistry.