Synthesis and characterization of an enhanced heterogeneous cation exchange membrane via nanoclay

Electrodialysis (ED) is a separation process based on the transport of ions through ion exchange membranes. Ion exchange membranes are the key factor of this system. In this research, PVC/HIPS/ABS blended heterogeneous cation exchange membranes were made by solution casting method using tetrahydrofuran as solvent and cation exchange resin. The blend of various ratios of these polymers was prepared, and the best ratio was selected as the polymeric matrix. Montmorillonite K10 nanoparticles (with cation exchange characteristics) were then added to the appropriate polymeric matrix to enhance the electrochemical properties of the membrane. All the electrochemical properties of the synthesized membranes (with and without additives) were investigated. Montmorillonite K10 particles enhanced the membrane properties due to their cation exchange capacity. The best results were obtained with PVC/ABS binder and 0.03 additive ratio, where the membrane electrical resistance was decreased 37% while the IEC and transport number were improved 75 and 6%, respectively.