Spacer geometry plays an important role in membrane separation processes. In electrodialysis, spacer geometry affects not only the pressure-driven flow but can also possibly influence the local electric-field profile and with that the induced electro-osmotic flow by the spacer.
We previously demonstrated that using polyelectrolyte-coated spacers gave higher ionic currents for the same driving force, underscoring the additional electro-osmotic mixing from using spacers with charged surfaces. In this study, we expand this work to check the effect of electro-osmotic mixing in combination with spacers having different flow attack angles. We have compared, experimentally, the performance of ED using surface-charged spacers with three different flow attack angles. Our results showed that the spacers with 45$\degree$ flow attack angle outperformed the spacers with 30$\degree$ and 90$\degree$ flow attack angle when using uncoated spacers for certain applied voltage (3 to 8V). On the other hand, an improved effect of a charged coating was mostly observed for the spacer with a 45$\degree$ flow attack angle.
" 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: J.A. (Jeffery) orcid: "https://orcid.org/0000-0002-9438-1048" title: "Data underlying research for Effect of flow attack angle on spacer-induced electrokinetics in electrodialysis" keywords: version: 1 identifiers: - type: doi value: 10.4121/2e540aef-452e-47ec-92db-9b9792830d3a.v1 license: CC0 date-released: 2023-09-08