Highly conductive anion exchange membrane with a stable double-sided anti-fouling structure for electrodialysis desalination of protein systems

作者：Wang, Juan; Liu, Manru; Feng, Zihao; Liu, Jinshuai; Liao, Shijun; Li, Xiuhua^*; Yu, Yigang^*

来源：Desalination, 2023, 545: 116167.

DOI：10.1016/j.desal.2022.116167

• Electrodialysis
• Anion exchange membrane
• Ca-Na alginate
• Double -sided anti -fouling
• Protein

To provide a durable anti-fouling electrodialysis (ED) anion exchange membrane for desalination of systems containing protein, a method of double-sided in-situ interpenetrating of a highly conductive ionomer to pre-made anti-fouling Ca-Na alginate (CA) films has been developed. Three highly conductive AEMs (QPPO-DABCO-CAs) with various hydrophilicity were successfully fabricated by tuning the lateralized gradient cross-linked structures of CA films and well-controlling ion exchange capacity (IEC) of series-connected 1,4-diazabicyclo[2.2.2] octane (DABCO) di-cations group functionalized poly(2,6-dimethyl-1,4-phenylene oxide) (QPPO-DABCO). QPPODABCO-CAs have significant anti-fouling effects on protein type foulant and qualified basic and electro properties for ED applications. The results of the ED desalination and ED stability evaluations at salted duck egg white system further confirm that QPPO-DABCO-CA(2% SA-0.10Ca) with suitable interpenetration structure surpasses commercial AMX and displays the highest current efficiency (eta) of 84.86 %, the highest salt flux (J) of 51.40 mg m- 2 s- 1, the lowest energy consumption (EC) of 0.83 kWh kg- 1, and better ED desalination stability. Protein biuret detections verify that the protein fouling on the dense AEMs is surface-fouling. The properties of QPPODABCO-CA(2% SA-0.10Ca) are promising for ED desalination of organic macromolecule protein-rich salt aqueous systems.