Cation exchange membrane integrated with cationic and anionic layers for selective ion separation via electrodialysis

• Published in: Desalination Vol. 458; pp. 25 - 33
• Main Authors: Afsar, Noor Ul, Shehzad, Muhammad Aamir, Irfan, Muhammad, Emmanuel, Kamana, Sheng, Fangmeng, Xu, Tingting, Ren, Xuemei, Ge, Liang, Xu, Tongwen
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.05.2019
• Subjects: Cation separation; Electrodialysis; Monovalent cation perm-selective membrane; PVA-based hybrid membranes; Cation separation; Monovalent cation perm-selective membrane; PVA-based hybrid membranes; Electrodialysis
• ISSN: 0011-9164; 1873-4464
• DOI: 10.1016/j.desal.2019.02.004

The advances of electrodialysis (ED) have been restricted by the trade-off between perm-selectivity and ion flux of ion exchange membranes. This article lucidly explains the fabrication of novel PVA-based hybrid membranes modified with cationic and anionic layers. Cationic layer is composed of quaternized poly (2, 6-dimethyl-1, 4-phenylene oxide), while anionic layer is sulfonated poly (2, 6-dimethyl-1, 4-phenylene oxide). Interestingly, the perm-selectivity of Li+/Mg2+via ED was observed up to 5.16 with a feed concentration of 0.1 mol L−1 LiCl/MgCl2 at 2.12 mA cm−2 current density. Electrochemical impedance spectroscopy was used to get further insight about the membrane and solution interfaces such as the influence of a base membrane and the deposited layers, which showed the perm-selective behavior of the modified membranes. The observed high perm-selectivity of modified membranes will step forward the ED applications for production of salts and treatment of saline water comprising monovalent and divalent cations. •LBL approach was adopted to prepare monovalent cation perm-selective membranes.•The prepared membranes unveiled good perm-selectivity for cations separation.•EIS and IV analyses provide further insights into membrane surface characteristics.