Abstract
Most commercial anion exchange membranes (AEMs) deploy quaternary ammonium moieties. Alternative cation moieties have been explored in AEMs for fuel cells, but there are no studies focused examining alternative tethered cations in AEMs for ionic separations-such as organic acid anion transport via electrodialysis. H-cell and conductivity experiments demonstrate that tethered benzyl 1-methyl imidazolium groups in polysulfone AEMs enhance lactate conductivity by 49% and improved lactate anion flux by 24x when compared to a quaternary benzyl ammonium polysulfone AEM. An electrodialysis demonstration with the imidazolium-type AEM showed a 2x improvement in lactate anion flux and 20% improvement in permselectivity when benchmarked against the quaternary ammonium AEM. Molecular dynamics and 2D NOESY NMR revealed closer binding of lactate anions to the imidazolium cations when compared to the quaternary ammonium cation. It is posited that this closer binding is responsible to greater flux values observed with imidazolium-type AEM.
| Original language | English (US) |
|---|---|
| Article number | 043511 |
| Journal | Journal of the Electrochemical Society |
| Volume | 169 |
| Issue number | 4 |
| DOIs | |
| State | Published - Apr 1 2022 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Materials Chemistry
- Surfaces, Coatings and Films
- Electrochemistry
- Renewable Energy, Sustainability and the Environment