cff-version: 1.2.0
abstract: "<p>The boundary layer thickness within the fluid channels strongly determines the performance of electrodialysis (ED) processes since it controls the rate of ion transport. Reducing the boundary layer thickness through more efficient mixing allows for reducing the energy input to achieve the same current or higher currents for the same driving potential. In our previous work, we studied the electrokinetic effects of spacers within a lab-scale ED stack by using polyelectrolyte coated spacers that create an electro-osmotic mixing effect that affects the boundary layer near the limiting current regime. In this work, we use a segmented electrode stack to explore how spacer-induced electrokinetic effects impact the evolution of the boundary layer along the length of a stack operating under constant driving potential. By using the segmented electrode system, we are able to show clear differences in the distribution of current (densities) along the stack length between the case with polyelectrolyte-coated spacers and non-coated spacers. Our results show that the use of surface-charged spacers in particular leads to higher current densities in highly ion-depleted regions of the stack (i.e. farther towards the stack outflow) and we attribute this current density increase to increased electro-osmotic mixing within the boundary layer. Additionally, we quantify the difference in spacer performance between the uncoated and coated case using a simple empirical formulation for current density distribution along the stack length.</p>"
authors:
  - family-names: Lammertink
    given-names: Rob
    orcid: "https://orcid.org/0000-0002-0827-2946"
  - family-names: Paul
    given-names: Arputha
    orcid: "https://orcid.org/0000-0001-9066-7076"
  - family-names: Wood
    given-names: Jeffery A.
title: "Data underlying research for A study on electrokinetic effects of spacers in ED using a segmented electrode stack"
keywords:
version: 1
identifiers:
  - type: doi
    value: 10.4121/e54a1b44-0a39-4c23-bc68-656a893bf613.v1
license: CC0
date-released: 2023-09-08