Development of piperidinium-grafted anion exchange membranes for desalination applications via electrodialysis process

Designing advanced membranes with efficient ion exchange capacity (IEC) is a critical necessity for addressing water scarcity through desalination. This study outlines the synthesis of anion exchange membranes (AEMs) incorporating N-methylpiperidine a tertiary amine by introducing varying proportions of N-methylpiperidine into brominated poly(2,6-dimethyl-1,4-phenylene oxide) (BPPO). The functionalities of these AEMs were evaluated using Fourier transform infrared (FTIR) spectroscopy, confirming the successful creation of piperidinium-grafted AEMs. The physico-chemical characterization of prepared AEMs revealed impressive properties, including tensile strength (TS) ranging from 12.10 to 22.96 MPa, elongation at break (Eb) between 18.20 and 31.89 %, area resistance spanning from 19.67 to 1.55 Ω.cm², transport numbers from 0.91 to 0.97, water uptake (WR) varying from 11.92 to 37.18 %, linear expansion ratio (LER) in the range of 4.10 to 17.86 %, and ion exchange capacity (IEC) ranging from 0.69 to 1.98 mmol/g. Additionally, these membranes exhibited a homogeneous morphology. To assess their desalination capabilities, selected AEMs (M3 & M4) underwent electrodialysis (ED) processes. Under identical experimental conditions, these AEMs demonstrated superior desalination efficiency compared to the commercial membrane Neosepta AMX, showcasing their potential for advancing desalination technologies. © © 2025. Published by Elsevier B.V.