N-cyclic cationic group-functionalized cardo poly(arylene ether sulfone)s membranes with ultrahigh selectivity for diffusion dialysis in acid recovery

• Published in: Journal of membrane science Vol. 624; p. 119115
• Main Authors: Gong, Feixiang, Fan, Zhitao, Xia, Wenke, Zhang, Meng, Wang, Lei, Wang, Xudong, Chen, Xinbing
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15-04-2021
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/j.memsci.2021.119115

To produce high-performance and durable membranes used in diffusion dialysis (DD) for acid recovery, poly(arylene ether sulfone)s containing different N-cyclic quaternary ammonium (QA) cations (CardoPES-C2-R(Cl-)) were prepared, and the relationships between the N-cyclic QAs and the properties of the corresponding membranes were explored. The CardoPES-C2-R(Cl-) membranes exhibited ultrahigh H+/Fe2+ selectivity in DD that was higher than that of a commercial DD membrane and other reported DD membranes. Most importantly, both the acid dialysis coefficient (UH+) and the H+/Fe2+ selectivity of the CardoPES-C2-R(Cl-) membranes can be readily adjusted by regulating the chemical structures of functional groups. Interestingly, because of the hydrogen bonds proven by 1H NMR, the CardoPES-C2-Mor(Cl-) membrane displayed a higher acid permeability coefficient than other N-cyclic QA cation-based membranes with identical ion exchange capacity (IEC) values, but showed lower Cl- conductivity. Additionally, the CardoPES-C2-R(Cl-) membranes exhibited excellent chemical and operational stability after aging testing and consecutive operation.
[Display omitted]
•Cardo poly(arylene ether sulfone)s containing different N-Cyclic QAs were prepared.•Membranes morphology could be controlled by adjusting the structure of N-Cyclic QAs.•The membranes exhibited ultrahigh H+/Fe2+ selectivity in diffusion dialysis (DD).