Theory of membrane capacitive deionization including the effect of the electrode pore space
P.M. Biesheuvel,Ran Zhao,S. Porada,A. van der Wal +3 more
- Vol. 360, Iss: 1, pp 239-248
TLDR
An extended theory for MCDI is set up which includes in the description for the porous electrodes not only the electrostatic double layers formed inside the porous (carbon) particles, but also incorporates the role of the transport pathways in the electrode, i.e., the interparticle pore space.Abstract:
Membrane capacitive deionization (MCDI) is a technology for water desalination based on applying an electrical field between two oppositely placed porous electrodes Ions are removed from the water flowing through a channel in between the electrodes and are stored inside the electrodes Ion-exchange membranes are placed in front of the electrodes allowing for counterion transfer from the channel into the electrode, while retaining the coions inside the electrode structure We set up an extended theory for MCDI which includes in the description for the porous electrodes not only the electrostatic double layers (EDLs) formed inside the porous (carbon) particles, but also incorporates the role of the transport pathways in the electrode, ie, the interparticle pore space Because in MCDI the coions are inhibited from leaving the electrode region, the interparticle porosity becomes available as a reservoir to store salt, thereby increasing the total salt storage capacity of the porous electrode A second advantage of MCDI is that during ion desorption (ion release) the voltage can be reversed In that case the interparticle porosity can be depleted of counterions, thereby increasing the salt uptake capacity and rate in the next cycle In this work, we compare both experimentally and theoretically adsorption/desorption cycles of MCDI for desorption at zero voltage as well as for reversed voltage, and compare with results for CDI To describe the EDL-structure a novel modified Donnan model is proposed valid for small pores relative to the Debye lengthread more
Citations
More filters
Journal ArticleDOI
Review on the science and technology of water desalination by capacitive deionization
TL;DR: Capacitive deionization (CDI) as mentioned in this paper is a promising technology for energy-efficient water desalination using porous carbon electrodes, which is made of porous carbons optimized for salt storage capacity and ion and electron transport.
Journal ArticleDOI
Water desalination via capacitive deionization : What is it and what can we expect from it?
TL;DR: Capacitive deionization (CDI) is an emerging technology for the facile removal of charged ionic species from aqueous solutions, and is currently being widely explored for water desalination applications.
Journal ArticleDOI
Desalination via a new membrane capacitive deionization process utilizing flow-electrodes
Sungil Jeon,Hong-ran Park,Jeong-gu Yeo,SeungCheol Yang,Churl-Hee Cho,Moon Hee Han,Dong Kook Kim +6 more
TL;DR: In this paper, a capacitive deionization process utilizing flow-electrodes (FCDI) was designed and evaluated for use in seawater desalination, which exhibited excellent removal efficiency (95%) with respect to an aqueous NaCl solution (salt concentration: 32.1 g L−1), demonstrating that the FCDI process could effectively overcome the limitations of typical CDI processes.
Journal ArticleDOI
Direct prediction of the desalination performance of porous carbon electrodes for capacitive deionization
S. Porada,Lars Borchardt,Martin Oschatz,Marek Bryjak,Jennifer S. Atchison,Karel J. Keesman,Stefan Kaskel,P.M. Biesheuvel,Volker Presser,Volker Presser +9 more
TL;DR: In this paper, the effect of pore size distributions on salt electrosorption capacity and salt removal rate in carbide-derived carbons has been studied experimentally and theoretically.
Journal ArticleDOI
Energy consumption and constant current operation in membrane capacitive deionization
TL;DR: In this paper, the authors proposed a different operational mode for MCDI, whereby desalination is driven by a constant electrical current, which leads to a constant salt concentration in the desalinated stream over long periods of time.
References
More filters
Journal ArticleDOI
Materials for electrochemical capacitors
TL;DR: This work has shown that combination of pseudo-capacitive nanomaterials, including oxides, nitrides and polymers, with the latest generation of nanostructured lithium electrodes has brought the energy density of electrochemical capacitors closer to that of batteries.
Journal ArticleDOI
Science and technology for water purification in the coming decades
Mark A. Shannon,Paul W. Bohn,Paul W. Bohn,Menachem Elimelech,Menachem Elimelech,John G. Georgiadis,Benito J. Mariñas,Anne M. Mayes,Anne M. Mayes +8 more
TL;DR: Some of the science and technology being developed to improve the disinfection and decontamination of water, as well as efforts to increase water supplies through the safe re-use of wastewater and efficient desalination of sea and brackish water are highlighted.
Journal ArticleDOI
Capacitive deionization as an electrochemical means of saving energy and delivering clean water. Comparison to present desalination practices: Will it compete?
TL;DR: Capacitive deionization (CDI) is an electrochemical water treatment process that holds the promise of not only being a commercially viable alternative for treating water but for saving energy as well as mentioned in this paper.
Journal ArticleDOI
Energy issues in desalination processes.
TL;DR: The current energy consumption of different desalination processes is reviewed and a comparison with other common energy-consuming ventures leads to some interesting conclusions.