Dual Functional Layers Modified Anion Exchange Membranes with Improved Fouling Resistant for Electrodialysis

Abstract

The fouling mitigation of anion exchange membrane (AEM) performance is a great challenge faced by many membrane applications (e.g., electrodialysis, ED). In this study, a novel AEM is modified with dual functional layers prepared by coating hydrophilic polydopamine (PDA) on quaternized poly(2,6‐dimethyl‐1,4‐phenylene oxide), and subsequently grafting with zwitterionic structure of sulfobetaine methacrylate via the aza‐Michael reaction, aiming to improve the membrane fouling resistant. In particular, the sodium dodecyl benzene sulfonate (SDBS) is used as model foulant. The hydrophilic layer (PDA) and hydrophilic/negatively charged zwitterionic surface of AEM, act as useful barriers via physical blocking and electrostatic repulsion, respectively. The proposed modification can restrict the deposition and/or chemical adsorption of SDBS. The time elapsed until the occurrence of fouling (transition time) is significantly enhanced as result of modification (around five times longer) as evidence of the reinforced antifouling property. The enhanced performance of modified membrane is also confirmed by desalting experiments in terms of NaCl rejection potential. The facile preparation and advanced performances of dual functional layers modified AEM suggest its potential ED application.

P4VP Modified Zwitterionic Polymer for the Preparation of Antifouling Functionalized Surfaces

“…Increasing DMAEMA amount of P4VP-co-PDMAEMA resulted in a decrease in roughness (P1 0.79 ± 0.08 nm, P2 0.70 ± 0.11 nm, P3 0.68 ± 0.12 nm, and P4 1.37 ± 0.87 nm), with similar results observed for P4VPPC-co-PDMAPC, the roughness values of CP20, CP40, and CP60 were 0.43 ± 0.09 nm, 0.41 ± 0.11 nm, and 0.44 ± 0.08 nm. These observations are consistent with previous results that high levels of CBMA produced films with more flexible hydrophilic side-chains that could decrease the roughness of the film surface [35,36].…”

Tailoring the Surface Chemistry of Anion Exchange Membranes with Zwitterions: Toward Antifouling RED Membranes

“… 29 , 34 − 38 On the other hand, PDA in the form of a thin layer on a membrane surface is a versatile platform for membrane modification thanks to its functional groups that can undergo further reactions. 39 , 40 …”

“…Although frequently studied in water purification applications, Ruan et al provided the only example to date of zwitterionic surface modification of an ion exchange membrane with polysulfobetaine to induce fouling resistance, showing promising results during electrodialysis (ED) of a solution containing sodium dodecylbenzenesulfonate (SDBS) as model foulant, although their investigation spans a limited time scale (2 h) only. 39 …”

Fabrication and Optical Modeling of Micro‐Porous Membranes Index‐Matched with Water for On‐Line Sensing Applications

“…Micro‐porous membranes are widely used for several applications including filtering, separation, emulsification, reaction catalysis, analytical measurements, and fabric production. [ 1–7 ] Key membrane properties, such as filtering power, flow resistance and robustness, are determined by their internal structure. Moreover, degradation of membrane performance can be ascribed to structural modification or to incorporation of extrinsic particles or microorganisms that cause fouling or clogging.…”

“…Micro-porous membranes are widely used for several applications including filtering, separation, emulsification, reaction catalysis, analytical measurements, and fabric production. [1][2][3][4][5][6][7] Key membrane properties, such as filtering power, flow resistance and robustness, are determined by their internal structure. Moreover, degradation of membrane performance can be ascribed to membranes made by polytetrafluoroethylene (PTFE), have been extensively applied in several fields, from research applications to industrial processes, including water and waste water treatment, air filtration, membrane distillation, and pollutants removal.…”