Evaluation of the efficiency of brackish desalination ion exchange membranes using electrodialysis process

Abstract

In this study, polysulfone (PSu) was functionalized and modified using resin and fiber reinforcements for the preparation of mono and bipolar ion exchange membranes. In the case of the bipolar membrane, platinum was used as the intermediate layer. A solution of NaCl in the brackish water concentration range from 5 g L⁻¹ to 25 g L⁻¹ was used as the feed solution for the desalting technique using an electrodialysis process. A commercially procured ion exchange membrane made of polystyrene divinyl benzene was also evaluated for the purpose of comparison. The BPMED performance reached a highest current efficiency of 82.5% and 53.6% with the energy consumption of 0.52 W h and 1.39 W h for the synthesized and commercial membranes respectively. Also the performance of the fabricated unit was assessed in terms of electrical conductivity, salinity and ion (sodium and chloride) concentrations for the feed solution after an 8 hour duration. The reproducibility performance of the membranes was also analyzed for the synthetic salt solution.