A chemically assembled anion exchange membrane surface for monovalent anion selectivity and fouling reduction

© 2019 The Royal Society of Chemistry. Separation and extraction of monovalent anions from salt lakes or oceans is very important in view of a sustainable supply of industrial chemical compounds. In this work, a novel anion exchange membrane (AEM) with simultaneously enhanced monovalent anion selectivity and reduced organic fouling properties was synthesized through oxidative self-polymerization and an amide condensation reaction. Using a rapid deposition and polymerization procedure, l-dopa was coated on a commercial AEM surface to form an l-dopa polymer layer (l-PDA) by using CuSO4 and H2O2 as a trigger. This layer was chemically assembled with a 4-amino-benzenesulfonic acid monosodium salt (ABS) via an amide condensation reaction. The resulting anion exchange membrane l-PDA#ABS, with a unique hydrophilic characteristic and negatively charged thin layer, was found to have a high monovalent anion permselectivity of 5.29 (SO42-/Br-) and 4.66 (SO42-/Cl-) in electrodialysis (ED) (10 min, initial concentration of 50 mM Br-, Cl- and SO42-, and current density of 10.00 mA cm-2), while the original AEM had corresponding permselectivities of 1.22 and 1.00. Furthermore, the selective separation efficiency parameter of the l-PDA#ABS AEM in SO42-/Br- and SO42-/Cl- was 66% and 63%, which is higher than those of the original AEM (8% and 2%). Sodium dodecyl benzene sulfonate, bovine serum albumin and humic acid were used as model organic fouling materials; the l-PDA#ABS AEM has a much higher antifouling potential than a commercial reference AEM. The work also demonstrated that the chemically assembled functional layer with high stability was suitable for long term application.

Jaar van publicatie:2019

BOF-keylabel:ja

IOF-keylabel:ja

BOF-publication weight:10

CSS-citation score:3

Auteurs:International

Authors from:Higher Education

Toegankelijkheid:Closed