Mitigating Water Crossover by Crosslinked Coating of Cation‐Exchange Membranes for Brine Concentration. Issue 10 (23rd June 2021)

• Record Type: Journal Article
• Authors: Rommerskirchen, Alexandra; Roth, Hannah; Linnartz, Christian J.; Egidi, Franziska; Kneppeck, Christian; Roghmans, Florian; Wessling, Matthias
• Is Part Of: Advanced materials technologies. Volume 6:Issue 10(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-06-23
• Subjects: brine concentration -- flow‐electrode capacitive deionization -- ion‐exchange membranes -- selective coating -- water desalination; Materials science -- Periodicals; Technological innovations -- Periodicals; Materials science; Technological innovations; Periodicals; 620.1105
• DOI: 10.1002/admt.202100202
• Languages: English
• ISSNs: 2365-709X

Abstract

Abstract: Undesired water crossover through ion‐exchange membranes is a significant limitation in electrically driven desalination processes. The effect of mitigating water crossover is twofold: 1) The desalination degree is less reduced due to the unwanted removal of water, and 2) the brine concentration is increased due to decreased dilution by an unwanted crossover of water molecules. Hence, water crossover limits the desalination and concentration efficiency of the processes, while the energy demand to achieve a certain level of desalination or concentration increases. This effect is especially pronounced when treating high salinity solutions, which goes hand in hand with the crossover of many ions through the ion‐exchange membranes. A crosslinked coating for cation‐exchange membranes (CEMs) is presented in this work, which can significantly mitigate such undesired water crossover. The efficacy is demonstrated using the flow‐electrode capacitive deionization process applied for desalination and concentration of saline brines at feed concentrations of 60 and 120 g L −1 NaCl. With just a single coated CEM, the water crossover was reduced by up to 54%. Abstract : Undesired water crossover through ion‐exchange membranes is a significant limitation in electrically driven desalination processes. A crosslinked coating on a cation‐exchange membrane (CEM) can significantly mitigate the water crossover. With the coated CEM, the water crossover was reduced by up to 54% under high salinity conditions in flow‐electrode capacitive deionization.