期刊
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
卷 164, 期 9, 页码 E270-E275出版社
ELECTROCHEMICAL SOC INC
DOI: 10.1149/2.1201709jes
关键词
-
资金
- Israeli Ministry of National Infrastructures, Energy and Water Resources
- Israel Science Foundation (ISF) of the Israel National Research Center for Electrochemical Propulsion (INREP) project
Capacitive deionization (CDI) is a fast-emerging technology most commonly applied to brackish water desalination. In typical CDI cells, dissolved ions are removed from the feedwater and stored in electric double layers (EDLs) within micropores of electrically charged porous carbon electrodes. Recent experiments have demonstrated that porous carbon CDI electrodes exhibit selective ion removal based on ion size, with the smaller ion being preferentially removed in the case of equal-valence ions. However, state-of-the-art CDI theory does not capture this observed selectivity, as it assumes volume-less point ions in the micropore EDLs. We here present a theory which includes multiple counterionic species, and relaxes the point ion assumption by incorporating ion volume exclusion interactions into a description of the micropore EDLs. The developed model is a coupled set of nonlinear algebraic equations which can be solved for micropore ion concentrations and electrode Donnan potential at cell equilibrium. We show that our model predicts the non-unity separation factor observed experimentally in CDI systems with two equal-valence counterions, which could not be explained by previous CDI theory. Further, our theory captures the measured values of the separation factor when using the hard-sphere diameter as an adjustable parameter. (C) The Author(s) 2017. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives 4.0 License (CC BY-NC-ND, http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial reuse, distribution, and reproduction in any medium, provided the original work is not changed in any way and is properly cited. For permission for commercial reuse, please email: oa@ electrochem. org. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据