The Hydration of Acrylonitrile to Produce Acrylamide Using Biocatalyst in Micro-Dispersed System

The hydration of acrylonitrile to produce acrylamide using biocatalyst in micro-dispersed system

Jiahui Li, Yang Chen, Jianhong Xu, Yujun Wang*, Guangsheng Luo

State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China

The bioconversion of acrylonitrile to acrylamide catalyzed by NHase is attracting attention because it is performed under mild reaction conditions and presents various advantages such as the low energy consumption, safe bioprocess, and high purity. However, acrylonitrile and acrylamide have double inhibition on the enzyme activity.

Previous work has proved that membrane dispersion microreactor was suitable for the hydration of acrylonitrile to produce acrylamide.

In this work, acrylonitrile was used as a dispersed phase, pure free-resting cell solution was set as continuous phase and a co-axial microfluidic device was utilized to control diameters of the dispersed droplets and discuss the influence of flow and reaction on mass transfer. Through observation using a microscopy, it was found that the acrylonitrile was dispersed into droplets with a diameter ranged from 160 to 60 mm. It was found that increasing the flow rate of continuous phase is advantageous to the dissolution of acrylonitrile droplets into cell solution at the formation stage of the droplets. In addition, intensifying factor (I) was calculated and I decreased as the flow rate of the continuous phase increased, indicating that strengthening the convection under high continuous phase velocity is the key to accelerate the mass transfer.