Development of monopolar and platinum intermediate bipolar membranes: application in desalting brine solution

The desalination process parameters like current efficiency (CE), energy consumption, and acid–base production for the fabricated bipolar membrane (BPM) electrodialysis unit (five compartments of 120 cm2 active areas) were investigated in this paper using monopolar- and bipolar-based ion-exchange membranes (IEMs). Also, the performance of the fabricated unit in removing NaCl was assessed in terms of salinity. Polystyrene–ethylene–butylene–polystyrene was functionalized to prepare the monopolar and bipolar IEMs. In the case of BPM, platinum was used as the intermediate layer. The synthesized IEMs were characterized thermally and by contact angle measurements. A commercially procured monopolar and bipolar ion-exchange membrane made of polystyrene–divinylbenzene was also evaluated for the purpose of comparison. The electrodialysis process using these IEMs reached the highest CE of 66 and 38% with the lowest energy consumption of 0.24 Wh and 1.60 Wh for the synthesized and commercial membrane, respectively.