Preparation of bipolar membranes. II

Abstract

ABSTRACT:The bipolar multilayer membrane was prepared by a new technique. The interfacial layer and cation layer were formed by only one step. The anion and cation layers were made from the same material from which chloromethylated polysulfone was used as a basic material. The bipolar membranes were composed of a solventresistant anion layer with crosslinking matrix by the reaction of chloromethylated polysulfone in DMF with diamine; an ultrathin interfacial layer from chloromethylated polysulfone solution in DMF, containing cation-exchange resin and both quaternary and nonquaternary amine groups; and a cation layer from chloromethylated polysulfone dispersing cation resin powder. The prepared bipolar membrane exhibits a lower voltage drop over 100 mA/cm 2 and stable performances at a long-term operation.

Ion exchange membranes: State of their development and perspective

“…Among these, the casting method seems to be the most attractive one for preparing such membranes because it is simple, less costly and also allows a bipolar membrane with desire prosperities for commercial use, such as good mechanical strength, ability to operate at high current density, high permselectivity, low potential drop, etc. [153]. Using this method and the basis of the homogeneous membrane preparation, a novel bipolar membrane has been prepared by casting the sulfonated PPO solution on a series anion exchange membranes as shown in Fig.…”

Ion Exchange Membranes for Electrodialysis: A Comprehensive Review of Recent Advances

“…For preparing bipolar membranes with suitable properties, various methods has been initiated, such as laminating polymeric films with fixed charges of opposite polarity with heat and pressure or with an adhesive paste [106], preparing by casting a cation exchange polyelectrolyte solution onto an anion exchange membrane or vice-versa [107], or preparing from the same base membrane by simultaneous functionalizing at the two membrane sides [108] or selectively functionalizing on one side to give cation selectivity and on the other side to give anion selectivity [109], etc. Among these, the casting method is the most efficient one for the preparation of such membrane because it is simple, less costly and also allows a bipolar membrane with desired properties [110]. Using this method, novel bipolar membranes have been prepared by casting the sulfonated PPO solution on a series anion exchange membranes [111].…”

Graphene Oxide–Polyaniline as a Water Dissociation Catalyst in the Interfacial Layer of Bipolar Membrane for Energy-Saving Production of Carboxylic Acids from Carboxylates by Electrodialysis

“…An efficient BPM should have good adhesion between different layers, mechanical strength, ability to operate at high current density, high permselectivity, and low potential drop . Generally, AEL are prepared via chloromethylation of polysulfone, poly­(etherimide), poly­(2,6-dimethyl-1,4-phenylene oxide) (PPO), and Cardo poly­(ether sulfone)-based polymer using chloromethyl ether (CME) followed by quaternization. − These preparative procedures are complicated, and in particular, CME is carcinogenic and potentially harmful to human health. , Recently, we reported a safe route of chloromethylation followed by amination for preparing a quaternized PPO-based anion-exchange membrane, which was used as AEL in this case to avoid the use of brominating agent and CME .…”