Study on the desalination and regeneration performance of PBA/AC electrode enhanced by membrane capacitor deionization

Abstract In this study, we investigate the desalination and regeneration performance of oilfield concentrated brine by the membrane capacitive deionization (MCDI) systems through batch experiments. Prussian blue analog (PBA) and active carbon (AC) electrodes is used in the MCDI cell. The influences of capacitive deionization on adsorption-desorption efficiency under optimal desorption conditions are analyzed. The experimental results show that the optimized operational parameters for achieving superior deionization regeneration performance in membrane capacitors comprise a voltage magnitude of -1.6 V, a desorption flow rate of 30 mL/min, and an electrode regeneration duration of 25 minutes. The MCDI system achieves a desorption amount of 45.87 mg/g, a remarkable regeneration rate of 99.23%, and an impressive desorption rate of 1.83 mg/(g·min) under the optimized operating conditions. The MCDI system demonstrates a desorption amount and regeneration rate that are 22.56 mg/g and 17.47% higher, respectively, compared to the Capacitive Deionization (CDI) system.