Effect of Operating Voltage on Organic Acid Recovery from Butyl-acrylate Wastewater with Bipolar Membrane Electrodialysis

A three-chambered bipolar membrane electrodialysis pilot module was used to recover organic acid from butyl-acrylate wastewater. Influence of operation voltage on the process was investigated. It was indicated that the operation voltage had significant effects on electrodialysis capacity, energy consumption and recovered organic acid concentration of the module. As the operation voltage increased from 50 V to 100 V, average current density increased from 16.91 mA/cm² to 55.22 mA/cm² linearly, and the electrodialysis duration was shortened significantly. Energy consumption for organic acid production increased from 0.10 kW·h/mol to 0.20 kW·h/mol linearly. As the operation voltage increased from 50 V to 100 V, water migrating with organic acid anion increased while that migrating with sodium cation decreased. As a result, higher organic acid concentration and lower NaOH concentration were achieved at operation voltage of 50 V.