Large Scale Preparation of Polyethylene Based Ion Exchange Membranes and Their Application for Water Desalination

Summary Here in we are reporting the large scale preparation and characterization of polyethylene (PE) based interpolymer ion exchange membranes (IEMs) and their performance evaluation during water desalination by electrodialysis. The cation exchange membrane (CEM) has been prepared from cross-linked PE/polystyrene interpolymer film and the anion exchange membrane (AEM) has been prepared from cross-linked PE/polypmethylstyrene based interpolymer film by suitable functionalization reaction. Both the prepared CEM and AEM exhibited 1.5–1.30 meq g−1 ion-exchange capacity, 2.85–1.15 m Scm−1 ionic conductivity and 0.92–0.93 transport number respectively. The prepared AEM and CEM were used for brackish water desalination containing total solid content (2000–3000 mg/L) by electrodialysis in a unit of size 200 cm2 using 30 pieces of each kind of membrane under single pass mode with final flow of purified water 7.2–8.4 L/h. The power consumption (W) and current efficiency (CE %) of the desalination processes were 0.789–0.796 kWh/kg and 87–86% respectively. On the contrary the W and CE% values were 1.125–1.07 kWh/kg and 61–64% for commercial IONSEP membranes during water desalination under similar experimental condition. These values indicate the better performance of developed membranes and established the validation of the process in large scale.