High performance electrochemical saline water desalination using silver and silver-chloride electrodes

Electrochemical desalination technologies such as capacitive deionization (CDI) and battery desalination (BD) are considered as promising brackish water desalination technologies because of their low energy consumption and environmental friendliness. However, it is a still challenge to develop an efficient way to deionize highly concentrated salt water using these technologies due to the limited desalination capacity. Here, we demonstrate how a system consisting of anion selective two-phase reaction battery electrodes combined with a cation exchange membrane shows a much higher capacity (approx. 85 mg g−1) along with remarkable salt removal efficiency (80%) while the cell voltage is still low (0.2 V). Moreover, with this system, it is possible to operate with high currents (100 A m−2) that are an order of magnitude higher than previous battery desalination systems.