Control of mixing in a continuous-flow microreactor with a varied gap width

Authors

  • Дмитрий Анатольевич Брацун (Dmitry A. Bratsun) Perm National Research Polytechnic University
  • Рамиль Рифгатович Сираев (Ramil R. Siraev) Perm National Research Polytechnic University

DOI:

https://doi.org/10.17072/1994-3598-2017-4-26-36

Abstract

Continuous-flow microreactors are at the center of the revolution that occurs in chemical engineering technology. The advantages of these new reactor types are: the quick and effective mixing of the reagents, very small reagent quantities used for the synthesis, the regulation of the main reaction parameters, i.e. flow rate, residence time, pressure and so on with very high accuracy. In this paper, a Hele-Shaw cell with a variable gap width is theoretically analyzed as the main element of the flow reactor of more advanced type. As a test reaction, we consider the reaction of neutralization of nitric acid with sodium hydroxide occurring in water, which leads, as it was previously demonstrated, to convective instability in the gravity field due to the effect of concentration-dependent diffusion (CDD instability). We show that the equations of motion are, in general, analogous to the fluid filtration equations in a porous medium (Darcy problem) with the variable permeability. We demonstrate numerically that the prototyping the spatially-distributed shape of the reactor zone can successfully separate the incoming and outgoing flows of reagents, control the intensity of the mixing processes locally, increase or decrease the value of the product of the outlet. The possibility of controlling the chemo-hydrodynamic flows in a reactor in real time through a local change in the width of the gap is also discussed.

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Published

2017-12-28

How to Cite

Брацун (Dmitry A. Bratsun) Д. А., & Сираев (Ramil R. Siraev) Р. Р. (2017). Control of mixing in a continuous-flow microreactor with a varied gap width. Bulletin of Perm University. Physics, (4(38). https://doi.org/10.17072/1994-3598-2017-4-26-36

Issue

Section

Regular articles