Novel synthetic route to prepare doubly quaternized anion exchange membranes for diffusion dialysis application

摘要

Graphical abstractDisplay OmittedHighlights?Anion exchange membranes (AEMs) were prepared from double quaternization and sol–gel reaction.?The membranes demonstrated excellent physicochemical properties.?The membranes showed high separation performance for acid recovery by diffusion dialysis.AbstractIn this work, anion exchange membranes (AEMs) were prepared from double quaternization and sol–gel reaction of synthesized anion exchange precursor and polyvinyl alcohol (PVA). The anion exchange precursor was the result of alkylation reaction of 1,6-Dibromohexane on 1,4-Diazabicyclo[2.2.2]octane (DABCO) and ring opening reaction by 3-glycidoxypropyltrimethoxysilane. The prepared membranes showed good physicochemical properties. The water uptakes were in the range of 82.6–148.5% while the ion exchange capacities (IECs) were in the range of 0.61–0.86mmol/g. The membranes demonstrated high mechanical strengths and thermal stabilities. Tensile strengths (TS) were in the range of 15.4–22.7MPa while Ebvalues were in the range of 441.2–541.0%. Those membranes were tested in diffusion dialysis (DD) for recovery of acid by using a simulated waste solution of HCl/FeCl2mixture (1MHCl+0.25M FeCl2). The results reveal higher acid dialysis coefficients (UH) between 30.0 and 44.9m/h×10?3and separation factor (S) ranges of 20.9–32.3 which are greater than commercial membranes DF-120 (UH=9×m/h×10?3and S=18.5).]]>