Electrodialysis

In electrodialysis, ion exchange membranes (IEMs) are leveraged to separate streams by applying an electric field. IEMs are membranes that contain fixed electrically charged chemical groups, which block ions of the same charge (co-ions) and allow the transport of ions of the opposite charge (counter-ions). When organized in an alternating manner, as in a typical ED stack, applying an electric field drives an ionic current carried by the counter ions, resulting in the concentration of half of the channels and dilution of the other half.

Electrodialysis has the potential to perform ion-ion selective separations, as its performance is affected by both membrane processes and transport in the flow channels. In our lab, we focus on analyzing these different mechanisms, both numerically and experimentally.

Further reading:

• A paper comparing ion-ion selectivity by electrodialysis and electrosorption cells: Shocron et al., Environ. Sci. Technol. Lett., 2022, link: https://doi.org/10.1021/acs.estlett.2c00551
• A paper analyzing selectivity mechanisms in electrodialysis for the desalination of natural brackish water: Shocron et al., J. Membr. Sci., 2025, link: https://doi.org/10.1016/j.memsci.2024.123668