Theory of shock electrodialysis I: Water dissociation and electrosmotic vortices
Name
2012.05431.pdf
Description
Submitted version
Size
456.31 KB
Format
Adobe PDF
Checksum (MD5)
68b1b397ab442ff54dcbb413fd0252a5
Author(s)
Tian, Huanhuan
Alkhadra, Mohammad A
Bazant, Martin Z
Date Issued
2021
Journal
Journal of Colloid and Interface Science
Publisher
Elsevier BV
Version
Original manuscript
Abstract
Shock electrodialysis (shock ED), an emerging electrokinetic process for water purification, leverages the new physics of deionization shock waves in porous media. In previous work, a simple leaky membrane model with surface conduction can explain the propagation of deionization shocks in a shock ED system, but it cannot quantitatively predict the deionization and conductance (which determines the energy consumption), and it cannot explain the selective removal of ions in experiments. This two-part series of work establishes a more comprehensive model for shock ED, which applies to multicomponent electrolytes and any electrical double layer thickness, captures the phenomena of electroosmosis, diffusioosmosis, and water dissociation, and incorporates more realistic boundary conditions. In this paper, we will present the model details and show that hydronium transport and electroosmotic vortices (at the inlet and outlet) play important roles in determining the deionization and conductance in shock ED. We also find that the results are quantitatively consistent with experimental data in the literature. Finally, the model is used to investigate design strategies for scale up and optimization.
MIT Department
Massachusetts Institute of Technology. Department of Mathematics
Massachusetts Institute of Technology. Department of Chemical Engineering
Terms of Use
Creative Commons Attribution-NonCommercial-NoDerivs License
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1016/j.jcis.2020.12.125
