Utilizing Advanced Bipolar Membranes in Next Generation Electrodialysis Systems

Abstract

Bipolar membranes (BPMs) have experienced a renaissance, owing to their proposed use in membrane electrode assembly (MEA) systems. MEA systems encompass technologies such as fuel cells and electrolyzers, where the BPM allows for fine pH control at the electrodes and helps to prevent ion-crossover that may lead to lower system efficiencies and fouling of the system. The exploration of MEA systems has significantly expanded our fundamental understanding of BPM functionality and limits, setting the stage for future advancements in BPM applications.Beyond MEA systems, BPMs have been seen in a wide array of technologies such as CO2 sequestration systems, electrodialysis, brine remediation, organic acid/base production, and more. These applications all present unique stressor to the BPM that prevent the direct translation of advanced, MEA optimized BPM to these non-MEA systems. Initial investigations into transferring advanced BPM to non-MEA applications have found issues with membrane delamination at scale and a need for system specific catalyst optimization. However, the fundamentals learned from MEA systems translate well and can be used to inform advancements of BPM in these non-MEA systems. Here we present initial findings and proposed solutions for durability issues when optimizing advanced BPM for application in BPM electrodialysis.