Capacitive deionization (CDI) removes ions from solution using charged electrodes. CDI has demonstrated significant energy savings compared with reverse osmosis for removal of salt from brackish water. By tailoring electrode properties such as pore morphology and surface functionality, as well as cell operating parameters, selective separation of ions can be achieved (e.g., selective absorption of nitrate in the presence of chloride and sulfate ions). The selective removal of toxic ions from otherwise potable water has the potential to dramatically reduce the cost of water treatment. Here, we will present the latest work from Lawrence Livermore National Laboratory on selective ion removal using our unique flow-through electrode CDI platform, including the development of a multi-scale model (FE + QMD) to help elucidate the mechanism(s) for ion selectivity in CDI.

This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.