Ion selectivity in capacitive deionization with functionalized electrode: Theory and experimental validation.

ABSTRACT: Capacitive deionization (CDI) is a promising technique for salt removal and may have potential for highly selective removal of ion species. In this work, we take advantage of functional groups usually used with ionic exchange resins and apply these to CDI. To this end, we functionalize activated carbon with a quaternary amines surfactant and use this surface to selectively and passively (no applied field) trap nitrate ions. We then set the cell voltage to a constant value to regenerate these electrodes, resulting in an inverted capacitive deionization (i-CDI) operation. Unlike resins, we avoid use of concentrated chemicals for regeneration. We measure the selectivity of nitrate versus chloride ions as a function of regeneration voltage and initial chloride concentration. We experimentally

SUBMITTER: Oyarzun DI 

PROVIDER: S-EPMC6549908 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature