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Mass transfer in falling film microreactors: measurement techniques and effect of operational parameters

Ali Alhafiz Mohammed and David Lokhat


Falling film microreactors have contributed to the pursuit of process intensification strategies and have, over the years, been recognized for their potential in performing demanding reactions. In the last few decades, modifications in the measurement techniques and operational parameters of these microstructured devices have been the focus of many research studies with a common target on process improvement. In this work, we present a review dedicated to falling film microreactors, focusing on the recent advances in their design and operation, with particular emphasis on mass transfer enhancement. Analysis of the recent techniques for the measurement of mass transfer as well as the operational parameters used and their effect on the target objective, particularly in the liquid phase (being the limiting phase reactant), are included in the review. The relationship between the hydrodynamics of falling thin liquid films and the microreactor design, the discrepancies between measured and model results, the major challenges, and the future outlook for these promising microreactors are also presented.

Funding source: National Research Foundation of South Africa

Award Identifier / Grant number: 99339

Funding statement: This work is based on research supported in part by the National Research Foundation of South Africa, unique grant no. 99339.

  1. Conflict of interest: The authors confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome.


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Received: 2018-09-10
Accepted: 2019-04-10
Published Online: 2019-06-29
Published in Print: 2021-02-23

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