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He Z, Miller CJ, Zhu Y, Wang Y, Fletcher J, Waite TD. Membrane capacitive deionization (MCDI): A flexible and tunable technology for customized water softening. WATER RESEARCH 2024; 259:121871. [PMID: 38852388 DOI: 10.1016/j.watres.2024.121871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 05/20/2024] [Accepted: 06/02/2024] [Indexed: 06/11/2024]
Abstract
There is a growing demand for water treatment systems for which the quality of feedwater in and product water out are not necessarily fixed with "tunable" technologies essential in many instances to satisfy the unique requirements of particular end-users. For example, in household applications, the optimal water hardness differs for particular end uses of the supplied product (such as water for potable purposes, water for hydration, or water for coffee or tea brewing) with the inclusion of specific minerals enhancing the suitability of the product in each case. However, conventional softening technologies are not dynamically flexible or tunable and, typically, simply remove all hardness ions from the feedwater. Membrane capacitive deionization (MCDI) can potentially fill this gap with its process flexibility and tunability achieved by fine tuning different operational parameters. In this article, we demonstrate that constant-current MCDI can be operated flexibly by increasing or decreasing the current and flow rate simultaneously to achieve the same desalination performance but different productivity whilst maintaining high water recovery. This characteristic can be used to operate MCDI in an energy-efficient manner to produce treated water more slowly at times of normal demand but more rapidly at times of peak demand. We also highlight the "tunability" of MCDI enabling the control of effluent hardness over different desired ranges by correlating the rates of hardness and conductivity removal using a power function model. Using this model, it is possible to either i) soften water to the same hardness level regardless of the fluctuation in hardness of feed waters, or ii) precisely control the effluent hardness at different levels to avoid excessive or insufficient hardness removal.
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Affiliation(s)
- Zhizhao He
- UNSW Centre for Transformational Environmental Technologies, Yixing, Jiangsu Province 214206, PR China; School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Christopher J Miller
- School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Yunyi Zhu
- UNSW Centre for Transformational Environmental Technologies, Yixing, Jiangsu Province 214206, PR China; School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Yuan Wang
- UNSW Centre for Transformational Environmental Technologies, Yixing, Jiangsu Province 214206, PR China; School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - John Fletcher
- School of Electrical Engineering and Telecommunications, UNSW Sydney, Sydney 2052, Australia
| | - T David Waite
- UNSW Centre for Transformational Environmental Technologies, Yixing, Jiangsu Province 214206, PR China; School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
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Luo L, Liu T, He J, Ma J, Yu HQ. Ion-Selective Metathesis Design of Flow-Electrode Capacitive Deionization for Energy-Saving and Anti-Scaling Softening of Brackish Water. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:13120-13130. [PMID: 38985512 DOI: 10.1021/acs.est.4c03227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/12/2024]
Abstract
While flow-electrode capacitive deionization (FCDI) is recognized as an attractive desalination technology, its practical implementation has been hindered by the ease of scaling and energy-intensive nature of the single-cell FCDI system, particularly when treating brackish water with elevated levels of naturally coexisting SO42- and Ca2+. To overcome these obstacles, we propose and design an innovative ion-selective metathesis FCDI (ISM-FCDI) system, consisting of a two-stage tailored cell design. Results indicate that the specific energy consumption per unit volume of water for the ISM-FCDI is lower (by up to ∼50%) than that of a conventional single-stage FCDI due to the parallel circuit structure of the ISM-FCDI. Additionally, the ISM-FCDI benefits from a conspicuous disparity in the selective removal of ions at each stage. The separate storage of Ca2+ and SO42- by the metathesis process in the ISM-FCDI (46.25% Ca2+, 14.25% SO42- in electrode 1 and 4.75% Ca2+, 35.25% SO42- in electrode 2) can effectively prevent scaling. Furthermore, configuration-performance analysis on the ion-selective migration suggests that the properties of the ion exchange membrane, rather than the carbon species, govern the selectivity of ion removal. This work introduces system-level enhancements aimed at enhancing energy conservation and scaling prevention, providing critical optimization of the FCDI for brackish water softening.
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Affiliation(s)
- Liang Luo
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Technology, University of Science and Technology of China, Hefei 230026, China
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Tao Liu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Jiazhou He
- Guangdong Basic Research Center of Excellence for Ecological Security and Green Development, Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
| | - Jinxing Ma
- Guangdong Basic Research Center of Excellence for Ecological Security and Green Development, Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
| | - Han-Qing Yu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Technology, University of Science and Technology of China, Hefei 230026, China
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Zhang H, Pang B, Di A, Chang J, Héraly F, Sikdar A, Pang K, Guo X, Li J, Yuan J, Zhang M. Harnessing Holey MXene/Graphene Oxide Heterostructure to Maximize Ion Channels in Lamellar Film for High-Performance Capacitive Deionization. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2403518. [PMID: 39016114 DOI: 10.1002/smll.202403518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2024] [Indexed: 07/18/2024]
Abstract
2D Ti3C2Tx MXene-based film electrodes with metallic conductivity and high pseudo-capacitance are of considerable interest in cutting-edge research of capacitive deionization (CDI). Further advancement in practical use is however impeded by their intrinsic limitations, e.g., tortuous ion diffusion pathway of layered stacking, vulnerable chemical stability, and swelling-prone nature of hydrophilic MXene nanosheet in aqueous environment. Herein, a nanoporous 2D/2D heterostructure strategy is established to leverage both merits of holey MXene (HMX) and holey graphene oxide (HGO) nanosheets, which optimize ion transport shortcuts, alleviate common restacking issues, and improve film's mechanical and chemical stability. In this design, the nanosized in-plane holes in both handpicked building blocks build up ion diffusion shortcuts in the composite laminates to accelerate the transport and storage of ions. As a direct outcome, the HMX/rHGO films exhibit remarkable desalination capacity of 57.91 mg g-1 and long-term stability in 500 mg L-1 NaCl solution at 1.2 V. Moreover, molecular dynamics simulations and ex situ wide angle X-ray scattering jointly demonstrate that the conductive 2D/2D networks and ultra-short ion diffusion channels play critical roles in the ion intercalation/deintercalation process of HMX/rHGO films. The study paves an alternative design concept of freestanding CDI electrodes with superior ion transport efficiency.
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Affiliation(s)
- Hao Zhang
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, P. R. China
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, 10691, Sweden
| | - Bo Pang
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, 10691, Sweden
| | - Andi Di
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, 10691, Sweden
| | - Jian Chang
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, 10691, Sweden
| | - Frédéric Héraly
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, 10691, Sweden
| | - Anirban Sikdar
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, 10691, Sweden
| | - Kanglei Pang
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, 10691, Sweden
| | - Xin Guo
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, P. R. China
| | - Jiansheng Li
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, P. R. China
| | - Jiayin Yuan
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, 10691, Sweden
| | - Miao Zhang
- Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, 10691, Sweden
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Yang K, Qin M. Enhancing selective ammonium transport in membrane electrochemical systems. WATER RESEARCH 2024; 257:121668. [PMID: 38692262 DOI: 10.1016/j.watres.2024.121668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2024] [Revised: 04/09/2024] [Accepted: 04/22/2024] [Indexed: 05/03/2024]
Abstract
Recovering ammonia nitrogen from wastewater is a sustainable strategy that simultaneously addresses both nitrogen removal and fertilizer production. Membrane electrochemical system (MES), which utilizes electrochemical redox reactions to transport ammonium ions through cation exchange membranes, has been considered as an effective technology for ammonia recovery from wastewater. In this study, we develop a mathematical model to systematically investigate the impact of co-existing ions on the transport of ammonium (NH4+) ions in MES. Our analysis elucidates the importance of pH values on both the NH4+ transport and inert ion (Na+) transport. We further comprehensively assess the system performance by varying the concentration of Na+ in the system. We find that while the inert cation in the initial anode compartment competes with NH4+ transport, NH4+ dominates the cation transport in most cases. The transport number of Na+ surpasses NH4+ only if the fraction of Na+ to total cation is extremely high (>88.5%). Importantly, introducing Na+ ions into the cathode compartment significantly enhances the ammonia transport due to the Donnan dialysis. The analysis of selective ion transport provides valuable insights into optimizing both selectivity and efficiency in ammonia recovery from wastewater.
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Affiliation(s)
- Kai Yang
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Mohan Qin
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI 53706, United States.
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Guan Y, Liu M, Liu Y, Yue J, Liu S, Gao W, Liang J. Improved desalination performance of flow-electrode capacitive deionisation by a novel drop-shape channel. ENVIRONMENTAL TECHNOLOGY 2024:1-11. [PMID: 38753489 DOI: 10.1080/09593330.2024.2354124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 04/04/2024] [Indexed: 05/18/2024]
Abstract
As an emerging desalination technology, flow-electrode capacitive deionisation (FCDI) has the advantages of theoretically infinite adsorption capacity and applicability to high-concentration brine. However, during the operation of FCDI, the flow electrode in the S-shape channel is prone to sedimentation and clogging the channel. This undesirable phenomenon brings low efficiency and security issues. Therefore, a drop-shape channel was designed for FCDI to improve the flow regime of the flow electrode. The flow simulation of the drop-shape channel was performed to select the appropriate geometry to avoid the formation of the vortex and low-velocity region. The simulation results showed that the streamlined design of the drop-shape channel has insignificant velocity gradients. It significantly reduces the low-velocity region and improves the phenomenon of particle sedimentation. The desalination performance with varieties of electrode flow rate, AC content, and voltage was used to investigate the advantage between S-shape and drop-shape channels. It was found that under the conditions of low flow rate, high AC content, and high voltage, the drop-shape channel FCDI system could still obtain better ASRR and CE.
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Affiliation(s)
- Yinyan Guan
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
| | - Mingxi Liu
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
| | - Yutong Liu
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
| | - Jinyu Yue
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
| | - Shiyue Liu
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
| | - Weichun Gao
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
| | - Jiyan Liang
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
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Shan W, Zi Y, Chen H, Li M, Luo M, Oo TZ, Lwin NW, Aung SH, Tang D, Ying G, Chen F, Chen Y. Coupling redox flow desalination with lithium recovery from spent lithium-ion batteries. WATER RESEARCH 2024; 252:121205. [PMID: 38301527 DOI: 10.1016/j.watres.2024.121205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 01/24/2024] [Accepted: 01/25/2024] [Indexed: 02/03/2024]
Abstract
Electrochemical redox flow desalination is an emerging method to obtain freshwater; however, the costly requirement for continuously supplying and regenerating redox species limits their practical applications. Recycling of spent lithium-ion batteries is a growing challenge for their sustainable utilization. Existing battery recycling methods often involve massive secondary pollution. Here, we demonstrate a redox flow system to couple redox flow desalination with lithium recovery from spent lithium-ion batteries. The spontaneous reaction between a battery cathode material (LiFePO4) and ferricyanide enables the continuous regeneration of the redox species required for desalination. Several critical operating parameters are optimized, including current density, the concentrations of redox species, salt concentrations of brine, and the amounts of added LiFePO4. With the addition of 0.5920 g of spent LiFePO4 in five consecutive batches, the system can operate over 24 h, achieving 70.46 % lithium recovery in the form of LiCl aqueous solution at the concentration of 6.716 g·L-1. Simultaneously, the brine (25 mL, 10000 ppm NaCl) was desalinated to freshwater. Detailed cost analysis shows that this redox flow system could generate a revenue of ¥ 13.66 per kg of processed spent lithium-ion batteries with low energy consumption (0.77 MJ kg-1) and few greenhouse gas emissions indicating excellent economic and environmental benefits over existing lithium-ion battery recycling technologies, such as pyrometallurgical and hydrometallurgical methods. This work opens a new approach to holistically addressing water and energy challenges to achieve sustainable development.
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Affiliation(s)
- Wei Shan
- School of Electronics and Information Engineering, South China Normal University, Foshan 528225, China
| | - Yang Zi
- School of Electronics and Information Engineering, South China Normal University, Foshan 528225, China
| | - Hedong Chen
- School of Electronics and Information Engineering, South China Normal University, Foshan 528225, China
| | - Minzhang Li
- School of Electronics and Information Engineering, South China Normal University, Foshan 528225, China
| | - Min Luo
- School of Chemistry and Chemical Engineering, Ningxia University, Yinchuan, Ningxia 750021, China
| | - Than Zaw Oo
- Department of Physics, Materials Research Laboratory, University of Mandalay, Mandalay 05032, Myanmar
| | - Nyein Wint Lwin
- Department of Physics, Materials Research Laboratory, University of Mandalay, Mandalay 05032, Myanmar
| | - Su Htike Aung
- Department of Physics, Materials Research Laboratory, University of Mandalay, Mandalay 05032, Myanmar
| | - Danling Tang
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Guangguo Ying
- Environmental Research Institute/School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, Guangdong 510006, China
| | - Fuming Chen
- School of Electronics and Information Engineering, South China Normal University, Foshan 528225, China.
| | - Yuan Chen
- School of Chemical and Biomolecular Engineering, The University of Sydney, Darlington, New South Wales 2006, Australia.
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Zhang X, Pang M, Wei Y, Liu F, Zhang H, Zhou H. Three-dimensional titanium mesh-based flow electrode capacitive deionization for salt separation and enrichment in high salinity water. WATER RESEARCH 2024; 251:121147. [PMID: 38277832 DOI: 10.1016/j.watres.2024.121147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 01/12/2024] [Accepted: 01/14/2024] [Indexed: 01/28/2024]
Abstract
Flow electrode capacitive deionization (FCDI) is a highly promising desalination technique known for its exceptional electrosorption capacity, making it suitable for efficient salt separation in high salinity water. However, the unsatisfactory charge transfer process between the flow electrode and current collector severely curtails the salt separation and enrichment performance of the FCDI device. To address this issue, three-dimensional titanium mesh (3D-TM) was proposed as a novel current collector for FCDI device, which significantly amplifies the charge transfer area and exhibits excellent salt separation performance. The 3D-TM current collector promotes the electron transfer, charge percolation, and ion migration processes through the electroconvection generated by the turbulence effect on the flow electrode. In the specific case of the 20-mesh 3D-TM, which is composed of 12 stacking layers of titanium mesh, the remarkable average salt removal rate and charge efficiency were achieved 5.06 μmol cm-2 min-1 and 92.9 % under an appropriate applied voltage of 2.0 V, respectively. Dramatically, the desalination performance maintained above 76.4 % over 100 desalination cycles at 2.0 V, demonstrating the exceptional cyclic stability of the 3D-TM FCDI cell. In the seawater desalination, the 3D-TM FCDI cell exhibited an impressive salt removal efficiency of 97.5 % (from 34.2 g L-1 to 0.84 g L-1) for 1 L East China seawater at 2.0 V for 24 h. For lithium-ion enrichment, the FCDI continuous desalting system achieved an astonishing concentration of 17.3 g L-1 for Li+ ions enrichment from an initial concentration of 1.30 g L-1, obtaining the average salt treating rate of 23.6 g m-2h-1 and charge efficiency of 80.0 %. Moreover, the lithium-sodium ions and lithium-magnesium ions enrichments were both conducted, yielding an enriched concentration of 10.4 g L-1 and 7.30 g L-1 for Li+ ions, respectively. These findings highlight the enormous potential of FCDI technology in industrial engineering applications, further establishing it as a highly viable solution.
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Affiliation(s)
- Xinyuan Zhang
- Key Laboratory of Materials Physics, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China; Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China
| | - Mengdie Pang
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China
| | - Yanan Wei
- Key Laboratory of Materials Physics, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
| | - Fei Liu
- Key Laboratory of Materials Physics, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
| | - Haimin Zhang
- Key Laboratory of Materials Physics, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China; Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China.
| | - Hongjian Zhou
- Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, China; Salt Lake Chemical Engineering Research Complex, Qinghai University, Xining 810016, China.
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Zhang W, Xue W, Zhang C, Xiao K. Towards long-term operation of flow-electrode capacitive deionization (FCDI): Optimization of operating parameters and regeneration of flow-electrode. Heliyon 2024; 10:e24940. [PMID: 38312617 PMCID: PMC10834994 DOI: 10.1016/j.heliyon.2024.e24940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 01/11/2024] [Accepted: 01/17/2024] [Indexed: 02/06/2024] Open
Abstract
This study systematically optimized the key operating parameters and interpreted their effecting mechanisms in a flow-electrode capacitive deionization (FCDI) system. The optimal voltage, activated carbon electrode content, electrolyte concentration, feedwater flowrate, and electrode flowrate for desalinating low salinity feedwater (1.0 g L-1 NaCl) were determined to be 1.8 V, 2.0 wt%, 10.0 g L-1, 80 mL min-1, and 60 mL min-1, respectively. The variations of the above parameters can affect the system conductivity, the thickness and stability of the electric double layers, and/or the degree of concentration polarization, thereby influencing the desalination performance. Moreover, a sensitivity analysis identified the operating voltage as the dominant parameter with the most significant influence on the FCDI system. Subsequently, a long-term operation was carried out under single-pass mode. The results showed that the lab-scale FCDI system was able to constantly maintain the desalination efficiency of 1.0 g L-1 feedwater (NaCl) at 40-60 % for multiple operating cycles. Over 99.8 % of electrode material regeneration and desalination efficiency recovery was able to be obtained during a 60-h operation, demonstrating that the FCDI system showed strong stability and long-term operation potential.
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Affiliation(s)
- Wanni Zhang
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani, 12120, Thailand
| | - Wenchao Xue
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani, 12120, Thailand
| | - Chunpeng Zhang
- Key Laboratory of Groundwater Resources and Environment (Ministry of Education), College of New Energy and Environment, Jilin University, Changchun, 130021, China
| | - Kang Xiao
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
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Sun X, Hao Z, Zhou X, Chen J, Zhang Y. Advanced capacitive deionization for ion selective separation: Insights into mechanism over a functional classification. CHEMOSPHERE 2024; 346:140601. [PMID: 37918536 DOI: 10.1016/j.chemosphere.2023.140601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 10/28/2023] [Accepted: 10/30/2023] [Indexed: 11/04/2023]
Abstract
Due to the diversity and variability of harmful ions in polluted water bodies, the selective removal and separation for specific ions is of great significance in water purification and resource processes. Capacitive deionization (CDI), an emerging desalination technology, shows great potential to selectively remove harmful ionic pollutants and further recover valuable ions because of the simple operation and low energy consumption. Researchers have done a lot of work to investigate ion selectivity utilizing CDI, including both theoretical and experimental studies. Nevertheless, in the investigation of selective mechanisms, phenomena where carbon materials exhibit entirely opposite selectivity require further analysis. Furthermore, there is a need to summarize the specific chemical reaction mechanisms, including the formation of hydrogen bonds, complexation reactions, and ligand exchanges, within selective electrodes, which have not been thoroughly examined in detail previously. In order to fill these gaps, in this review, we summarized the recent progress of CDI technologies for ion selective separation, and explored the selective separation mechanism of CDI from three aspects: selective physical adsorption, specific chemical reaction, and the utilization of selective barriers. Additionally, this review analyzes in detail the formation process of chemical bonds and ion conversion pathways when ions interact with electrode materials. Finally, some significant development prospects and challenges were offered for the future selective CDI systems. We believe the review will provide new insights for researchers in the field of ion selective separation.
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Affiliation(s)
- Xiaoqi Sun
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Zewei Hao
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Xuefei Zhou
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Jiabin Chen
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
| | - Yalei Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
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Sun J, Garg S, Waite TD. A Novel Integrated Flow-Electrode Capacitive Deionization and Flow Cathode System for Nitrate Removal and Ammonia Generation from Simulated Groundwater. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:14726-14736. [PMID: 37721968 DOI: 10.1021/acs.est.3c03922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/20/2023]
Abstract
Electrochemical reduction of nitrate is a promising method for the removal of nitrate from contaminated groundwater. However, the presence of hardness cations (Ca2+ and Mg2+) in groundwaters hampers the electroreduction of nitrate as a result of the precipitation of carbonate-containing solids of these elements on the cathode surface. Thus, some pretreatment process is required to remove unwanted hardness cations. Herein, we present a proof-of-concept of a novel three-chambered flow electrode unit, constituting a flow electrode capacitive deionization (FCDI) unit and a flow cathode (FC) unit, which achieves cation removal, nitrate capture and reduction, and ammonia generation in a single cell without the need for any additional chemicals/electrolyte. The addition of the FCDI unit not only achieves removal of hardness cations but also concentrates the nitrate ions and other anions, which facilitates nitrate reduction in the subsequent FC unit. Results show that the FCDI cell voltage influences electrode stability but has a minimal impact on the overall nitrate removal performance. The concentration of coexisting anions influences the nitrate removal due to competitive sorption of anions on the electrode surface. Our results further show that stable electrochemical performance was obtained over 26 h of operation. Overall, this study provides a scalable strategy for continuous nitrate electroreduction and ammonia generation from nitrate contaminated groundwaters containing hardness ions.
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Affiliation(s)
- Jingyi Sun
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Shikha Garg
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - T David Waite
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia
- UNSW Centre for Transformational Environmental Technologies, Yixing, Jiangsu Province 214206, P. R. China
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Xi J, Ming H, Liu S, Shen X, Geng C, Gao W, Meng J, Gao Y, Zhao Z, Lv J, Guan Y, Liang J. Effect of anion-exchange membrane type for FCDI performance at different concentrations. ENVIRONMENTAL TECHNOLOGY 2023; 44:3585-3591. [PMID: 35588316 DOI: 10.1080/09593330.2022.2064243] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 03/17/2022] [Indexed: 06/15/2023]
Abstract
Brackish water was an important alternative source of freshwater. Desalination using flow electrode capacitive deionization (FCDI) needs to explore the role of ion exchange membranes (IEM) of FCDI. In this study, brackish water was desalinated using FCDI, and anion exchange membranes with different characteristics were used in the FCDI cell to investigate their influence. The result showed that the membrane polymer matrix was the main influencing factor for ion transport. Ion exchange capacity (IEC) has a huge impact that low IEC made the various ion transport priority. Low IEC not only limits ion transport but also leads to ion leakage in seawater. Resistance had a significant blockage to the effect with weak intensity.
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Affiliation(s)
- Jingjun Xi
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
- Liaoning Province Research Center for Wastewater Treatment and Reuse, Shenyang, People's Republic of China
| | - Hao Ming
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
- Liaoning Province Research Center for Wastewater Treatment and Reuse, Shenyang, People's Republic of China
| | - Shiyue Liu
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
- Liaoning Province Research Center for Wastewater Treatment and Reuse, Shenyang, People's Republic of China
| | - Xinjun Shen
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
- Liaoning Province Research Center for Wastewater Treatment and Reuse, Shenyang, People's Republic of China
| | - Cong Geng
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
- Liaoning Province Research Center for Wastewater Treatment and Reuse, Shenyang, People's Republic of China
| | - Weichun Gao
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
- Liaoning Province Research Center for Wastewater Treatment and Reuse, Shenyang, People's Republic of China
| | - Jing Meng
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
- Liaoning Province Research Center for Wastewater Treatment and Reuse, Shenyang, People's Republic of China
| | - Yingjun Gao
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
- Liaoning Province Research Center for Wastewater Treatment and Reuse, Shenyang, People's Republic of China
| | - Zhongyuan Zhao
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
- Liaoning Province Research Center for Wastewater Treatment and Reuse, Shenyang, People's Republic of China
| | - Jiayu Lv
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
- Liaoning Province Research Center for Wastewater Treatment and Reuse, Shenyang, People's Republic of China
| | - Yinyan Guan
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
- Liaoning Province Research Center for Wastewater Treatment and Reuse, Shenyang, People's Republic of China
| | - Jiyan Liang
- School of Environmental and Chemical Engineering, Shenyang University of Technology, Shenyang, People's Republic of China
- Liaoning Province Research Center for Wastewater Treatment and Reuse, Shenyang, People's Republic of China
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12
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Elewa MM, El Batouti M, Al-Harby NF. A Comparison of Capacitive Deionization and Membrane Capacitive Deionization Using Novel Fabricated Ion Exchange Membranes. MATERIALS (BASEL, SWITZERLAND) 2023; 16:4872. [PMID: 37445186 DOI: 10.3390/ma16134872] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 07/05/2023] [Accepted: 07/05/2023] [Indexed: 07/15/2023]
Abstract
Another technique for desalination, known as membrane capacitive deionization (MCDI), has been investigated as an alternative. This approach has the potential to lower the voltage that is required, in addition to improving the ability to renew the electrodes. In this study, the desalination effectiveness of capacitive deionization (CDI) was compared to that of MCDI, employing newly produced cellulose acetate ion exchange membranes (IEMs), which were utilized for the very first time in MCDI. As expected, the salt adsorption and charge efficiency of MCDI were shown to be higher than those of CDI. Despite this, the unique electrosorption behavior of the former reveals that ion transport via the IEMs is a crucial rate-controlling step in the desalination process. We monitored the concentration of salt in the CDI and MCDI effluent streams, but we also evaluated the pH of the effluent stream in each of these systems and investigated the factors that may have caused these shifts. The significant change in pH that takes place during one adsorption and desorption cycle in CDI (pH range: 2.3-11.6) may cause problems in feed water that already contains components that are prone to scaling. In the case of MCDI, the fall in pH was only slightly more noticeable. Based on these findings, it appears that CDI and MCDI are promising new desalination techniques that has the potential to be more ecologically friendly and efficient than conventional methods of desalination. MCDI has some advantages over CDI in its higher salt removal efficiency, faster regeneration, and longer lifetime, but it is also more expensive and complex. The best choice for a particular application will depend on the specific requirements.
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Affiliation(s)
- Mahmoud M Elewa
- Arab Academy for Science, Technology and Maritime Transport, Alexandria P.O. Box 1029, Egypt
| | - Mervette El Batouti
- Chemistry Department, Faculty of Science, Alexandria University, Alexandria 21526, Egypt
| | - Nouf F Al-Harby
- Department of Chemistry, College of Science, Qassim University, Buraydah 51452, Saudi Arabia
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13
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Zhang W, Xue W, Xiao K, Visvanathan C, Tang J, Li L. Selection and optimization of carbon-based electrode materials for flow-electrode capacitive deionization. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2023.123649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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14
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Tan G, Wan S, Mei SC, Gong B, Qian C, Chen JJ. Boosted brackish water desalination and water softening by facilely designed MnO 2/hierarchical porous carbon as capacitive deionization electrode. WATER RESEARCH X 2023; 19:100182. [PMID: 37215310 PMCID: PMC10199261 DOI: 10.1016/j.wroa.2023.100182] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/30/2023] [Accepted: 05/09/2023] [Indexed: 05/24/2023]
Abstract
Capacitive deionization (CDI) is a promising technique for brackish water desalination. However, its salt electrosorption capacity is insufficient for practical application yet, and little information is available on hardness ion (Mg2+, Ca2+) removal in CDI. Herein, hierarchical porous carbon (HPC) was prepared from low-cost and renewable microalgae via a simple one-pot approach, and both MnO2/HPC and polyaniline/HPC (PANI/HPC) composites were then synthesized using a facile, one-step hydrothermal method. Compared with the MnO2 electrode, the MnO2/HPC electrode presented an improved hydrophilicity, higher specific capacitance, and lower electrode resistance. The electrodes exhibited pseudocapacitive behaviors, and the maximum salt electrosorption capacities of MnO2/HPC-PANI/HPC CDI cell was up to 0.65 mmol g-1 NaCl, 0.71 mmol g-1 MgCl2, and 0.76 mmol g-1 CaCl2, respectively, which were comparable and even higher than those of the previously reported CDI cells. Additionally, the MnO2/HPC electrode presented a selectivity order of Ca2+ ≥ Mg2+ > Na+, and the divalent cation selectivity was found to be attributed to their stronger binding strength in the cavity of MnO2. Multiscale simulations further reveal that the MnO2/HPC electrodes with the unique luminal configuration of MnO2 and HPC as supportive framework could offer a great intercalation selectivity of the divalent cations and exhibit a great promise in hardness ion removal.
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15
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Wang T, Zhang Z, Gu Z, Hu C, Qu J. Electron Transfer of Activated Carbon to Anode Excites and Regulates Desalination in Flow Electrode Capacitive Deionization. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:2566-2574. [PMID: 36719078 DOI: 10.1021/acs.est.2c09506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The desalination performance of flow electrode capacitive deionization (FCDI) is determined by the ion adsorption on the powdered activated carbon (PAC) and the electron transfer between the current collector and PAC. However, a comprehensive understanding of rate-limiting steps is lacking, let alone to enhance FCDI desalination by regulating the PAC characteristics. This study showed that the electron transfer between PAC and the current collector on the anode side was the rate-limiting step of FCDI desalination. Compared with W900, the desalination performance of FCDI decreased by 95% when W1200 with weak electron transfer ability was used as a flow electrode. The PAC selected in this study transferred electrons directly through the conductive carbon matrix in FCDI and was mainly affected by graphitization. The desalination performance of FCDI was improved by 20 times when the graphitization degree of PAC increased from 0.69 to 1.03. The minimum energy required for electrons to escape from the PAC surface was reduced by the high degree of graphitization, from 4.27 to 3.52 eV, thus improving the electron transfer capacity of PAC on the anode side. This study provides a direction for the optimization of flow electrodes and further promotes the development of FCDI.
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Affiliation(s)
- Tianyu Wang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing100085, China
- University of Chinese Academy of Sciences, Beijing100049, China
- National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Beijing100085, China
| | - Zijian Zhang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing100085, China
| | - Zhenao Gu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing100085, China
- University of Chinese Academy of Sciences, Beijing100049, China
- National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Beijing100085, China
| | - Chengzhi Hu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing100085, China
- University of Chinese Academy of Sciences, Beijing100049, China
- National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Beijing100085, China
| | - Jiuhui Qu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing100085, China
- University of Chinese Academy of Sciences, Beijing100049, China
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16
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Sun J, Garg S, Xie J, Zhang C, Waite TD. Electrochemical Reduction of Nitrate with Simultaneous Ammonia Recovery Using a Flow Cathode Reactor. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:17298-17309. [PMID: 36394539 DOI: 10.1021/acs.est.2c06033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The presence of excessive concentrations of nitrate in industrial wastewaters, agricultural runoff, and some groundwaters constitutes a serious issue for both environmental and human health. As a result, there is considerable interest in the possibility of converting nitrate to the valuable product ammonia by electrochemical means. In this work, we demonstrate the efficacy of a novel flow cathode system coupled with ammonia stripping for effective nitrate removal and ammonia generation and recovery. A copper-loaded activated carbon slurry (Cu@AC), made by a simple, low-cost wet impregnation method, is used as the flow cathode in this novel electrochemical reactor. Use of a 3 wt % Cu@AC suspension at an applied current density of 20 mA cm-2 resulted in almost complete nitrate removal, with 97% of the nitrate reduced to ammonia and 70% of the ammonia recovered in the acid-receiving chamber. A mathematical kinetic model was developed that satisfactorily describes the kinetics and mechanism of the overall nitrate electroreduction process. Minimal loss of Cu to solution and maintenance of nitrate removal performance over extended use of Cu@AC flow electrode augers well for long-term use of this technology. Overall, this study sheds light on an efficient, low-cost water treatment technology for simultaneous nitrate removal and ammonia generation and recovery.
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Affiliation(s)
- Jingyi Sun
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW2052, Australia
| | - Shikha Garg
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW2052, Australia
| | - Jiangzhou Xie
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW2052, Australia
- UNSW Centre for Transformational Environmental Technologies, Yixing, Jiangsu Province214206, P. R. China
| | - Changyong Zhang
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW2052, Australia
| | - T David Waite
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW2052, Australia
- UNSW Centre for Transformational Environmental Technologies, Yixing, Jiangsu Province214206, P. R. China
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17
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Han DC, Wang SY, Zhang CM, Yue RY, Wang SG, Sun XF. Efficient dual-ions hybrid capacitive system for superior deionization with enhanced kinetics match. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.141380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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18
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Chu M, Tian W, Zhao J, Zou M, Lu Z, Zhang D, Jiang J. A comprehensive review of capacitive deionization technology with biochar-based electrodes: Biochar-based electrode preparation, deionization mechanism and applications. CHEMOSPHERE 2022; 307:136024. [PMID: 35973487 DOI: 10.1016/j.chemosphere.2022.136024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 07/31/2022] [Accepted: 08/08/2022] [Indexed: 06/15/2023]
Abstract
The recently developed techniques for desalination and wastewater treatment are costly and unsustainable. Therefore, a cost-effective and sustainable approach is essential to achieve desalination through wastewater treatment. Capacitive deionization (CDI), an electrochemical desalination technology, has been developed as a novel water treatment technology with great potential. The electrode material is one of the key factors that promotes the development of CDI technology and broadens the scope of CDI applications. Biochar-based electrode materials have attracted increasing attention from researchers because of their advantages, such as environmentally friendly, economical, and renewable properties. This paper reviews the methods for preparing biochar-based electrode materials and elaborates on the mechanism of CDI ion storage. We then summarize the applications of CDI technology in water treatment, analyze the mechanism of pollutant removal and resource recovery, and discuss the applicability of different CDI configurations, including hybrid CDI systems. In addition, the paper notes that environmentally friendly green activators that facilitate the development of pore structure should be developed more often to avoid the adverse environmental impact. The development of ion-selective electrode materials should be enhanced and it is necessary to comprehensively assess the impact of heteroatoms on selective ion removal and CDI performance. Electrooxidation of organic pollutants should be further promoted to achieve organic degradation by extending to redox reactions.
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Affiliation(s)
- Meile Chu
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, PR China
| | - Weijun Tian
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, PR China; Key Laboratory of Marine Environment and Ecology, Ministry of Education, Qingdao 266100, PR China.
| | - Jing Zhao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, PR China
| | - Mengyuan Zou
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, PR China
| | - Zhiyang Lu
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, PR China
| | - Dantong Zhang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, PR China
| | - Junfeng Jiang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, PR China
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19
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Alkhadra M, Su X, Suss ME, Tian H, Guyes EN, Shocron AN, Conforti KM, de Souza JP, Kim N, Tedesco M, Khoiruddin K, Wenten IG, Santiago JG, Hatton TA, Bazant MZ. Electrochemical Methods for Water Purification, Ion Separations, and Energy Conversion. Chem Rev 2022; 122:13547-13635. [PMID: 35904408 PMCID: PMC9413246 DOI: 10.1021/acs.chemrev.1c00396] [Citation(s) in RCA: 59] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Agricultural development, extensive industrialization, and rapid growth of the global population have inadvertently been accompanied by environmental pollution. Water pollution is exacerbated by the decreasing ability of traditional treatment methods to comply with tightening environmental standards. This review provides a comprehensive description of the principles and applications of electrochemical methods for water purification, ion separations, and energy conversion. Electrochemical methods have attractive features such as compact size, chemical selectivity, broad applicability, and reduced generation of secondary waste. Perhaps the greatest advantage of electrochemical methods, however, is that they remove contaminants directly from the water, while other technologies extract the water from the contaminants, which enables efficient removal of trace pollutants. The review begins with an overview of conventional electrochemical methods, which drive chemical or physical transformations via Faradaic reactions at electrodes, and proceeds to a detailed examination of the two primary mechanisms by which contaminants are separated in nondestructive electrochemical processes, namely electrokinetics and electrosorption. In these sections, special attention is given to emerging methods, such as shock electrodialysis and Faradaic electrosorption. Given the importance of generating clean, renewable energy, which may sometimes be combined with water purification, the review also discusses inverse methods of electrochemical energy conversion based on reverse electrosorption, electrowetting, and electrokinetic phenomena. The review concludes with a discussion of technology comparisons, remaining challenges, and potential innovations for the field such as process intensification and technoeconomic optimization.
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Affiliation(s)
- Mohammad
A. Alkhadra
- Department
of Chemical Engineering, Massachusetts Institute
of Technology, Cambridge, Massachusetts 02139, United States
| | - Xiao Su
- Department
of Chemical and Biomolecular Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Matthew E. Suss
- Faculty
of Mechanical Engineering, Technion—Israel
Institute of Technology, Haifa 3200003, Israel,Wolfson
Department of Chemical Engineering, Technion—Israel
Institute of Technology, Haifa 3200003, Israel,Nancy
and Stephen Grand Technion Energy Program, Technion—Israel Institute of Technology, Haifa 3200003, Israel
| | - Huanhuan Tian
- Department
of Chemical Engineering, Massachusetts Institute
of Technology, Cambridge, Massachusetts 02139, United States
| | - Eric N. Guyes
- Faculty
of Mechanical Engineering, Technion—Israel
Institute of Technology, Haifa 3200003, Israel
| | - Amit N. Shocron
- Faculty
of Mechanical Engineering, Technion—Israel
Institute of Technology, Haifa 3200003, Israel
| | - Kameron M. Conforti
- Department
of Chemical Engineering, Massachusetts Institute
of Technology, Cambridge, Massachusetts 02139, United States
| | - J. Pedro de Souza
- Department
of Chemical Engineering, Massachusetts Institute
of Technology, Cambridge, Massachusetts 02139, United States
| | - Nayeong Kim
- Department
of Chemical and Biomolecular Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Michele Tedesco
- European
Centre of Excellence for Sustainable Water Technology, Wetsus, Oostergoweg 9, 8911 MA Leeuwarden, The Netherlands
| | - Khoiruddin Khoiruddin
- Department
of Chemical Engineering, Institut Teknologi
Bandung, Jl. Ganesha no. 10, Bandung, 40132, Indonesia,Research
Center for Nanosciences and Nanotechnology, Institut Teknologi Bandung, Jl. Ganesha no. 10, Bandung 40132, Indonesia
| | - I Gede Wenten
- Department
of Chemical Engineering, Institut Teknologi
Bandung, Jl. Ganesha no. 10, Bandung, 40132, Indonesia,Research
Center for Nanosciences and Nanotechnology, Institut Teknologi Bandung, Jl. Ganesha no. 10, Bandung 40132, Indonesia
| | - Juan G. Santiago
- Department
of Mechanical Engineering, Stanford University, Stanford, California 94305, United States
| | - T. Alan Hatton
- Department
of Chemical Engineering, Massachusetts Institute
of Technology, Cambridge, Massachusetts 02139, United States
| | - Martin Z. Bazant
- Department
of Chemical Engineering, Massachusetts Institute
of Technology, Cambridge, Massachusetts 02139, United States,Department
of Mathematics, Massachusetts Institute
of Technology, Cambridge, Massachusetts 02139, United States,
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20
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Xu L, Peng S, Wu K, Tang L, Wu M, Zong Y, Mao Y, Wu D. Precise manipulation of the charge percolation networks of flow-electrode capacitive deionization using a pulsed magnetic field. WATER RESEARCH 2022; 222:118963. [PMID: 35970008 DOI: 10.1016/j.watres.2022.118963] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 08/04/2022] [Accepted: 08/07/2022] [Indexed: 06/15/2023]
Abstract
Magnetic field is a simple and powerful means that enables controlled the transport of electrode particles in flow electrode capacitive deionization (FCDI). However, the magnetic particles are easily stripped from hybrid suspension electrodes and the precise manipulation of the charge percolation network remains challenging. In this study, a programmable magnetic field was introduced into the FCDI system to enhance the desalination performance and operational stability of magnetic FCDI, with core-shell magnetic carbon (MC) used as an alternative electrode additive. The results showed that the pulsed magnetic field (PMF) was more effective in enhancing the average salt removal rate (ASRR) compared to the constant magnetic field (CMF), with 51.6% and 67.7% enhancement, respectively, compared to the magnetic field-free condition. The outstanding advantage of the PMF lies in the enhancement in the trapping and mediating effects in the switching magnetic field, which keeps the concentration of the electrode particles near the current collector at a high level and greatly facilitates electron transport. In long-term operation (20,000 cycles), the pulsed magnetic FCDI achieved a stable desalinating rate of 0.4-0.68 μmol min-1 cm-2 and a charge efficiency of >96%. In brief, our study introduces a new approach for the precise manipulation of charge percolation networks of the suspension electrodes and provides insight into the charging mechanism of the magnetic FCDI.
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Affiliation(s)
- Longqian Xu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China
| | - Shuai Peng
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China
| | - Ke Wu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China
| | - Liang Tang
- Key Laboratory of Organic Compound Pollution Control Engineering (MOE), School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Minghong Wu
- Key Laboratory of Organic Compound Pollution Control Engineering (MOE), School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Yang Zong
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China
| | - Yunfeng Mao
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China; School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Deli Wu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China.
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21
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Zhang X, Zhou H, He Z, Zhang H, Zhao H. Flow-electrode capacitive deionization utilizing three-dimensional foam current collector for real seawater desalination. WATER RESEARCH 2022; 220:118642. [PMID: 35635913 DOI: 10.1016/j.watres.2022.118642] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 05/18/2022] [Accepted: 05/19/2022] [Indexed: 06/15/2023]
Abstract
The three-dimensional (3D) carbon coated nickel foam was utilized as current collector in a flow-electrode capacitive deionization (CF-FCDI) device to strengthen the charge transfer ability of FCDI device, achieving distinguished desalination efficiency for real seawater. Utilizing 30 ppi carbon coated nickel foam as current collector with 12.5 wt% AC content at 1.2 V to treat 3.5 g L-1 NaCl solution, the CF-FCDI achieved 99.8% of salt removal efficiency (SRE), 3.29 µmol cm-2 min-1 of average salt removal rate (ASRR) and 97.0% of charge efficiency (CE), surpassing most desalination performances in previous reports. Compared with the titanium mesh (TM-FCDI) and graphite plate (GP-FCDI) current collector, the three-dimensional electric field and computational fluid dynamics (CFD) simulations demonstrated that 3D foam current collector has obvious stronger competitiveness. Its intrinsic 3D interconnected open-pore structure as flow channel and 3D electric field could not only enlarge the charge contact area between the current collector and flow-electrode, but also eliminate the restriction of 0.75 mm effective charging range within the carbon slurry in traditional serpentine flow channels. Finally, the excellent desalination performance of CF-FCDI device was also verified by treating simulated seawater, real seawater samples from Yellow Sea and South China Sea with a high SRE of 99.9%, 99.8%, and 99.9%, respectively. This work introduced a new strategy for enhancing charge transfer ability and overall desalination efficiency of FCDI device by utilizing a novel 3D foam-structured current collector for real seawater desalination.
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Affiliation(s)
- Xinyuan Zhang
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031 PR China; Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, PR China
| | - Hongjian Zhou
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031 PR China; Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, PR China.
| | - Zhen He
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031 PR China
| | - Haimin Zhang
- Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031 PR China; Science Island Branch of Graduate School, University of Science and Technology of China, Hefei 230026, PR China.
| | - Huijun Zhao
- Centre for Clean Environment and Energy, Griffith University, Gold Coast Campus, QLD 4222, Australia
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22
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Xu L, Peng S, Mao Y, Zong Y, Zhang X, Wu D. Enhancing Brackish Water Desalination using Magnetic Flow-electrode Capacitive Deionization. WATER RESEARCH 2022; 216:118290. [PMID: 35306460 DOI: 10.1016/j.watres.2022.118290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 02/21/2022] [Accepted: 03/11/2022] [Indexed: 06/14/2023]
Abstract
Flow-electrode capacitive deionization (FCDI) is viewed as a potential alternative to the current state-of-the-art electrodriven technology for the desalination of brackish water. However, the key shortcoming of the FCDI is still the discontinuous nature of the electrode conductive network, resulting in low electron transport efficiency and ion adsorption capacity. Here, a novel magnetic field-assisted FCDI system (termed magnetic FCDI) is proposed to enhance brackish water desalination, simply by using magnetic activated carbon (MAC) as flow electrodes. The results show that the assistance from the magnetic field enables a 78.9% - 205% enhancement in the average salt removal rate (ASRR) compared with that in the absence of a magnetic field, which benefits from the artificial manipulation of the flow electrode transport behavior. In long-term tests, the stable desalination performance of magnetic FCDI was also demonstrated with a stable ASRR of 0.70 μmol cm-2 min-1 and energy-normalized removed salt (ENRS) of 8.77 μmol J-1. In addition, magnetic field also enables the regeneration of the electrode particles from the concentrated electrolyte. In summary, the findings indicate that the magnetic FCDI is an energy-efficient and operation convenient technology for brackish water desalination.
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Affiliation(s)
- Longqian Xu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China.
| | - Shuai Peng
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China.
| | - Yunfeng Mao
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China; School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, PR China.
| | - Yang Zong
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China.
| | - Xiaomeng Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China.
| | - Deli Wu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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Luo L, He Q, Chen S, Yang D, Chen Y. Metal-organic framework derived carbon nanoarchitectures for highly efficient flow-electrode CDI desalination. ENVIRONMENTAL RESEARCH 2022; 208:112727. [PMID: 35063431 DOI: 10.1016/j.envres.2022.112727] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 01/06/2022] [Accepted: 01/10/2022] [Indexed: 06/14/2023]
Abstract
Flow-electrode capacitive deionization (FCDI) has shown a robust desalination performance, in which the electrode materials play a crucial role. However, commercial activated carbon (AC) commonly with relatively poor conductivity, which can be a limit to the desalination process. To address this issue, we successfully prepared ZIF-8 derived nanocarbon materials (Zx, X = 0, 1, 2, 3, the number representing the activator ratio) via a pyrolysis activation procedure as electrode materials for FCDI desalination. The results manifested that Z3 achieved desalination rates of 0.0403 and 0.094 mg min-1 cm-2 in the isolated closed cycle (ICC) and the short-circuited closed cycle (SCC) mode, respectively, at 1.2 V with only 5 wt% carbon loading. The desalination rate of Z3 in the SCC mode was improved with flow rates and influent salt concentrations increase, reaching 0.278 mg min-1 cm-2 under a continuous operation. In the ICC mode, it was found that the adsorption capacity of the Zx sample was positively correlated with its specific surface area. The superior performance of Z3 could be attributed to the high conductivity, large specific surface area and well-developed pores. Overall, this work provided new insights and references for electrode material's application to FCDI desalination.
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Affiliation(s)
- Liang Luo
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400044, PR China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400044, PR China
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400044, PR China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400044, PR China.
| | - Siqi Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400044, PR China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400044, PR China
| | - Dongxu Yang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400044, PR China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400044, PR China
| | - Yi Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400044, PR China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400044, PR China.
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24
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Hu B, Shang X, Nie P, Zhang B, Yang J, Liu J. Lithium ion sieve modified three-dimensional graphene electrode for selective extraction of lithium by capacitive deionization. J Colloid Interface Sci 2022; 612:392-400. [PMID: 34999544 DOI: 10.1016/j.jcis.2021.12.181] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/27/2021] [Accepted: 12/28/2021] [Indexed: 11/18/2022]
Abstract
Faced with the strong demand of clean energy, development of lithium source is becoming exceedingly vital. Spinel-type manganese oxide (λ-MnO2) is a typical lithium ion sieve material. Herein, the conductive three-dimensional (3D) lithium ion sieve electrode material was fabricated by in-situ growth of λ-MnO2 on 3D reduced graphene oxide (3D-rGO) matrix for Li extraction by capacitive deionization (CDI). The λ-MnO2 modified rGO (λ-MnO2/rGO) retained the 3D network structure with uniform distribution of λ-MnO2 nanosheets on rGO. Electrochemical characterization demonstrated its high conductivity and fast lithium ion diffusion rate. By adjusting the rGO concentration, λ-MnO2 activity was improved significantly. With λ-MnO2/rGO as a positive electrode (activated carbon as negative electrode), the corresponding CDI system was successfully applied for the selective extraction of Li+. The final rGO content in the λ-MnO2/rGO was attained by thermogravity analysis. With the appropriate rGO content (15.5%), the obtained λ-MnO2/rGO electrode achieved the optimal Li+ adsorption amount. The corresponding λ-MnO2/rGO-based CDI cell showed good selectivity and high cycle stability. When applied to the extraction of lithium from synthetic salt lake brine, the electrode also obtained high Li+ adsorption amount with good selectivity.
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Affiliation(s)
- Bin Hu
- College of Environmental Science and Engineering, Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, Donghua University, Shanghai 201620, PR China
| | - Xiaohong Shang
- College of Environmental Science and Engineering, Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, Donghua University, Shanghai 201620, PR China
| | - Pengfei Nie
- College of Environmental Science and Engineering, Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, Donghua University, Shanghai 201620, PR China
| | - Boshuang Zhang
- College of Environmental Science and Engineering, Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, Donghua University, Shanghai 201620, PR China
| | - Jianmao Yang
- Research Center for Analysis & Measurement, Donghua University, Shanghai 201620, PR China
| | - Jianyun Liu
- College of Environmental Science and Engineering, Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, Donghua University, Shanghai 201620, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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25
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Yang Q, Xu L, He Q, Wu D. Reduced cathodic scale and enhanced electrochemical precipitation of Ca 2+ and Mg 2+ by a novel fenced cathode structure: Formation of strong alkaline microenvironment and favorable crystallization. WATER RESEARCH 2022; 209:117893. [PMID: 34872026 DOI: 10.1016/j.watres.2021.117893] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 06/13/2023]
Abstract
Electrochemical precipitation is a promising technique for hardness abatement without the addition of external ions. However, the scale layer on cathode deteriorated the removal efficiency and limited the practical application. Herein, a fenced cathode structure was designed to prevent cathodic precipitation. The cathode was fenced by a crystallization-inducing material for separating the OH- production and crystallization processes. Precipitation on the cathode was confirmed to shift to the crystallization-inducing material, and the clean fenced cathode provided efficient long-term OH- production. At a current density of 40 A/m2, the Ca2+ or Mg2+ removal efficiency increased by 12.8% or 46.1%, respectively, compared to those of a traditional cathode. Thermodynamic equilibrium in synthetic water and mine water, mass transfer and the location of precipitation were analyzed to elucidate the electrochemical precipitation process. The enhanced mechanism was ascribed to the crystallization-inducing material, which remarkably promoted the crystallization process, and hindered OH- migration, thereby increased the pH of alkaline microenvironment. Notably, a recovery design was proposed to recover pure calcite and brucite from alkalinity-free wastewater. The design reveals a promising strategy for enhancing the crystallization process and reducing cathodic scale, also initiating a new research direction toward hardness removal.
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Affiliation(s)
- Qianyuan Yang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China
| | - Longqian Xu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China
| | - Qunbiao He
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China
| | - Deli Wu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China.
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26
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Jiang H, Zhang J, Luo K, Xing W, Du J, Dong Y, Li X, Tang W. Effective fluoride removal from brackish groundwaters by flow-electrode capacitive deionization (FCDI) under a continuous-flow mode. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 804:150166. [PMID: 34517327 DOI: 10.1016/j.scitotenv.2021.150166] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 08/26/2021] [Accepted: 09/02/2021] [Indexed: 06/13/2023]
Abstract
Herein, we demonstrated the suitability and effectiveness of utilizing flow-electrode capacitive deionization (FCDI) for treatment of fluoride-contaminated brackish groundwater. By comparing operational modes of short-circuited closed-cycle (SCC), isolated closed-cycle (ICC) and single cycle (SC), it was found that SCC mode was the most advantageous. In SCC configuration, the effects of different parameters on the removal of F- and Cl- were investigated including current density, hydraulic residence time (HRT), activated carbon (AC) loading and feed concentration of coexisting NaCl. Results indicated that the steady-state effluent Cl- concentration dropped with elevated applied current, and the decreasing rate got faster with the increase of HRT or AC loading. However, for the steady-state effluent F- concentration, it dropped to a value under a small applied current and maintained stable in spite of the increase in applied current, and both HRT and AC loading had insignificant effects on the steady-state effluent F- concentration. F- was preferentially removed from the treated water compared with Cl-, and a higher ion selectivity could be obtained at lower applied current and smaller HRT with the trade-off being that operation under these circumstances would generate outlet water with little change in conductivity compared to the influent. The removal efficiencies of F- and Cl- both decreased with increasing feed concentration of coexisting NaCl. This study should be of value in establishing FCDI as a viable technology for treatment of fluoride-contaminated brackish groundwater.
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Affiliation(s)
- Huan Jiang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Jing Zhang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Kunyue Luo
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Wenle Xing
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Jiaxin Du
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Yi Dong
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Xiaoting Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China
| | - Wangwang Tang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, China.
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27
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Yu F, Yang Z, Cheng Y, Xing S, Wang Y, Ma J. A comprehensive review on flow-electrode capacitive deionization: Design, active material and environmental application. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2021.119870] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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28
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Zhou J, Zhang X, Zhang Y, Wang D, Zhou H, Li J. Effective inspissation of uranium(VI) from radioactive wastewater using flow electrode capacitive deionization. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2021.120172] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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29
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Pan Z, An J, Wang P, Fan X, Shen T, Xu R, Song Y, Song C. Novel strategy to enhance the desalination performance of flow-electrode capacitive deionization process via the assistance of electro-catalytic water splitting. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119753] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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30
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Yu C, Xu L, Mao Y, Zong Y, Wu D. Efficient recovery of carboxylates from the effluents treated by advanced oxidation processes using flow-electrode capacitive deionization in short-circuited closed-cycle operation. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119151] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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31
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Shen YY, Hsu CC, Tsai SW, Hou CH. Enhanced electrosorption selectivity of phosphate using an anion-exchange resin-coated activated carbon electrode. J Colloid Interface Sci 2021; 600:199-208. [PMID: 34015512 DOI: 10.1016/j.jcis.2021.04.129] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 04/25/2021] [Accepted: 04/26/2021] [Indexed: 10/21/2022]
Abstract
Regenerable methods for phosphate (P) recycling have received intense attention due to their potential environmental and economic benefits. In this study, to improve the electrosorptive removal of P in membrane capacitive deionization, an activated carbon (AC) electrode was coated with a heterogeneous anion-exchange resin layer, and named the AE-AC composite electrode. It was shown that the AE-AC electrode exhibited a good capacitive behavior for electrical double-layer charging. The batch-mode experiments indicted that when the solution pH changed from 5 to 8, the predominant P species shifted from monovalent H2PO4- to divalent HPO42- that was preferentially electroadsorbed for competitive electrosorption with Cl-. Importantly, the AE-AC composite electrode significantly increased the selectivity coefficient of P over Cl- to 0.56 that was 2.24-fold greater than that of the uncoated AC electrode, at 1.2 V in single-pass mode operation. This improvement can be ascribed to the preferential transport of P through the thin coating layer containing quaternary amine functional groups. The permselectivity of the coating also significantly increased the electrosorption capacity of P from 0.031 to 0.101 mmol/g with a high charge efficiency (97%) by the reduction in the co-ion repulsion effect. When the reverse voltage (-1.2 V) was applied, electroadsorbed P was reversibly desorbed from the AE-AC electrode in repeated operation. This work suggests that coating an anion-exchange resin layer on the surface of a carbon electrode shows great potential to improve the selective removal of P through electrosorption.
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Affiliation(s)
- Yu-Yi Shen
- Graduate Institute of Environmental Engineering, National Taiwan University, No.1, Sec. 4. Roosevelt Rd., Taipei 10617, Taiwan
| | - Chung-Chun Hsu
- Graduate Institute of Environmental Engineering, National Taiwan University, No.1, Sec. 4. Roosevelt Rd., Taipei 10617, Taiwan
| | - Shao-Wei Tsai
- Graduate Institute of Environmental Engineering, National Taiwan University, No.1, Sec. 4. Roosevelt Rd., Taipei 10617, Taiwan
| | - Chia-Hung Hou
- Graduate Institute of Environmental Engineering, National Taiwan University, No.1, Sec. 4. Roosevelt Rd., Taipei 10617, Taiwan; Water Innovation, Low Carbon and Environmental Sustainability Research Center, National Taiwan University, Taipei 10617, Taiwan.
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32
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Xu L, Mao Y, Zong Y, Peng S, Zhang X, Wu D. Membrane-Current Collector-Based Flow-Electrode Capacitive Deionization System: A Novel Stack Configuration for Scale-Up Desalination. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:13286-13296. [PMID: 34529405 DOI: 10.1021/acs.est.1c03829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The stack configuration in flow-electrode capacitive deionization (FCDI) has been verified to be an attractive and feasible strategy for scaling up the desalination process. However, challenges still exist when attempting to simultaneously improve the desalination scale and the cell configuration. Here, we describe a novel stack FCDI configuration (termed a gradient FCDI system) based on a membrane-current collector assembly, in which the charge neutralization enables the in situ regeneration of the flow electrodes in the single cycle operation, thereby realizing a considerable increase in the desalinating performance. By evaluating standardized metrics such as the salt rejection, productivity (P), average salt removal rate (ASRR), energy-normalized removed salt (ENRS), and TEE, the results indicated that the gradient FCDI system could be a performance-stable and energy-efficient alternative for scale-up desalination. Under optimal operating conditions (carbon content = 10 wt %, feed salinity = 3000 mg L-1, cell voltage = 1.2 V, and productivity = 56.7 L m-2 h-1), the robust desalination performance (ASRR = 1.07 μmol cm-2 min-1) and energy consumption (ENRS = 7.8 μmol J-1) of the FCDI system with a desalination unit number of four were verified at long-term operation. In summary, the stacked gradient FCDI system and its operation mode described here may be an innovative and promising strategy capable of enlarging the scale of desalination while realizing performance improvement and device simplification.
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Affiliation(s)
- Longqian Xu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China
| | - Yunfeng Mao
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China
| | - Yang Zong
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China
| | - Shuai Peng
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China
| | - Xiaomeng Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China
| | - Deli Wu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
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33
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Efficiency Enhancement of Electro-Adsorption Desalination Using Iron Oxide Nanoparticle-Incorporated Activated Carbon Nanocomposite. MICROMACHINES 2021; 12:mi12101148. [PMID: 34683201 PMCID: PMC8539726 DOI: 10.3390/mi12101148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/17/2021] [Accepted: 09/19/2021] [Indexed: 11/17/2022]
Abstract
Capacitive deionization (CDI) technology is currently considered a potential candidate for brackish water desalination. In this study, we designed iron oxide nanoparticle-incorporated activated carbon (AC/Fe2O3) via a facile and cost-effective hydrothermal process. The as-synthesized material was characterized using several techniques and tested as electrodes in CDI applications. We found that the distinctive properties of the AC/Fe2O3 electrode, i.e., high wettability, high surface area, unique structural morphology, and high conductivity, resulted in promising CDI performance. The electrosorptive capacity of the AC/Fe2O3 nanocomposite reached 6.76 mg g-1 in the CDI process, with a high specific capacitance of 1157.5 F g-1 at 10 mV s-1 in a 1 M NaCl electrolyte. This study confirms the potential use of AC/Fe2O3 nanocomposites as viable electrode materials in CDI and other electrochemical applications.
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34
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Luo L, He Q, Ma Z, Yi D, Chen Y, Ma J. In situ potential measurement in a flow-electrode CDI for energy consumption estimation and system optimization. WATER RESEARCH 2021; 203:117522. [PMID: 34384947 DOI: 10.1016/j.watres.2021.117522] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/28/2021] [Accepted: 08/02/2021] [Indexed: 06/13/2023]
Abstract
Flow electrode capacitive deionization (FCDI) is a promising electrochemical technique for brackish water desalination; however, there are challenges in estimating the distribution of resistance and energy consumption inside a FCDI system, which hinders the optimization of the rate-limiting compartment. In this study, energy consumption of each FCDI component (e.g., flow electrodes, membranes and desalination chamber) was firstly described by using in situ potential measurement (ISPM). Results of this study showed that the energy consumption (EC) of the flow electrodes dominated under most conditions. While an increase in the carbon black content in the flow electrodes could improve the energy efficiency of the electrode component, consideration should be given to the contribution of ion exchange membranes (IEMs) and the desalination chamber to the EC. Based on the above analysis, system optimization was carried out by introducing IEMs with relatively low resistance and/or packing the desalination chamber with titanium meshes. Results showed that the voltage-driven desalination capability was increased by 39.3% with the EC reduced by 17.5% compared to the control, which overcame the tradeoff between the kinetic and energetic efficiencies. Overall, the present work facilitates our understanding of the potential drops across an FCDI system and provides insight to the optimization of system design and operation.
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Affiliation(s)
- Liang Luo
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400044, PR China.; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing 400044, PR China
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400044, PR China.; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing 400044, PR China
| | - Zixin Ma
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400044, PR China.; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing 400044, PR China
| | - Duo Yi
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400044, PR China.; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing 400044, PR China
| | - Yi Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400044, PR China.; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing 400044, PR China..
| | - Jinxing Ma
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China.
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35
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He C, Lian B, Ma J, Zhang C, Wang Y, Mo H, Waite TD. Scale-up and Modelling of Flow-electrode CDI Using Tubular Electrodes. WATER RESEARCH 2021; 203:117498. [PMID: 34371229 DOI: 10.1016/j.watres.2021.117498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 07/09/2021] [Accepted: 07/27/2021] [Indexed: 06/13/2023]
Abstract
A novel design for a flow-electrode capacitive deionization (FCDI) system consisting of tubular electrodes in a shell and tube heat exchanger configuration is proposed. Each electrode consists of a metallic mesh current collector along the inner circumference of a tubular ion-exchange membrane. This tubular FCDI design is suitable for scale-up as it consists of easily manufactured components which can be assembled in an array. An apparatus with 4 tubular electrodes with a large effective area (202.3 cm2) was constructed and shown to provide a high net salt (NaCl) removal rate (0.15 mg s-1 at 1.2 V applied voltage and ∼2000 mg L-1 influent total dissolved solids concentration). A computational fluid dynamics (CFD) model incorporating ion migration and transport mechanisms was developed to simulate the ion concentration and electrical potential profiles in the water channel. The results of CFD modelling highlighted the need to maximize regions of both high potential gradient and high hydraulic flow in order to achieve optimal salt removal. In brief, this study presents a new design approach for FCDI scale-up and provides a computational tool for optimization of this design and future innovative FCDI designs.
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Affiliation(s)
- Calvin He
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Boyue Lian
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Jinxing Ma
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Changyong Zhang
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Yuan Wang
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Hengliang Mo
- Beijing Origin Water Membrane Technology Company Limited, Huairou, Beijing, 101400, P. R. China
| | - T David Waite
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
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36
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Yang F, He Y, Rosentsvit L, Suss ME, Zhang X, Gao T, Liang P. Flow-electrode capacitive deionization: A review and new perspectives. WATER RESEARCH 2021; 200:117222. [PMID: 34029869 DOI: 10.1016/j.watres.2021.117222] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 04/30/2021] [Accepted: 05/03/2021] [Indexed: 06/12/2023]
Abstract
Flow-electrode capacitive deionization (FCDI), as a novel electro-driven desalination technology, has attracted growing exploration towards brackish water treatment, hypersaline water treatment, and selective resource recovery in recent years. As a flow-electrode-based electrochemical technology, FCDI has similarities with several other electrochemical technologies such as electrochemical flow capacitors and semi-solid fuel cells, whose performance are closely coupled with the characteristics of the flow-electrodes. In this review, we sort out the potentially parallel mechanisms of electrosorption and electrodialysis in the FCDI desalination process, and make clear the importance of the flowable capacitive electrodes. We then adopt an equivalent circuit model to distinguish the resistances to ion transport and electron transport within the electrodes, and clarify the importance of electronic conductivity on the system performance based on a series of electrochemical tests. Furthermore, we discuss the effects of electrode selection and flow circulation patterns on system performance (energy consumption, salt removal rate), review the current treatment targets and system performance, and then provide an outlook on the research directions in the field to support further applications of FCDI.
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Affiliation(s)
- Fan Yang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yunfei He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Leon Rosentsvit
- Faculty of Mechanical Engineering, Technion - Israel Institute of Technology, Haifa, 32000, Israel
| | - Matthew E Suss
- Faculty of Mechanical Engineering, Technion - Israel Institute of Technology, Haifa, 32000, Israel; Faculty of Chemical Engineering, Technion - Israel Institute of Technology, Haifa, 32000, Israel.
| | - Xiaori Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Tie Gao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Peng Liang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
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Yang K, Qin M. The Application of Cation Exchange Membranes in Electrochemical Systems for Ammonia Recovery from Wastewater. MEMBRANES 2021; 11:membranes11070494. [PMID: 34208972 PMCID: PMC8305737 DOI: 10.3390/membranes11070494] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 06/22/2021] [Accepted: 06/28/2021] [Indexed: 11/16/2022]
Abstract
Electrochemical processes are considered promising technologies for ammonia recovery from wastewater. In electrochemical processes, cation exchange membrane (CEM), which is applied to separate compartments, plays a crucial role in the separation of ammonium nitrogen from wastewater. Here we provide a comprehensive review on the application of CEM in electrochemical systems for ammonia recovery from wastewater. Four kinds of electrochemical systems, including bioelectrochemical systems, electrochemical stripping, membrane electrosorption, and electrodialysis, are introduced. Then we discuss the role CEM plays in these processes for ammonia recovery from wastewater. In addition, we highlight the key performance metrics related to ammonia recovery and properties of CEM membrane. The limitations and key challenges of using CEM for ammonia recovery are also identified and discussed.
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Affiliation(s)
| | - Mohan Qin
- Correspondence: ; Tel.: +1-(608)-265-9733
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Zhang C, Ma J, Wu L, Sun J, Wang L, Li T, Waite TD. Flow Electrode Capacitive Deionization (FCDI): Recent Developments, Environmental Applications, and Future Perspectives. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:4243-4267. [PMID: 33724803 DOI: 10.1021/acs.est.0c06552] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
With the increasing severity of global water scarcity, a myriad of scientific activities is directed toward advancing brackish water desalination and wastewater remediation technologies. Flow-electrode capacitive deionization (FCDI), a newly developed electrochemically driven ion removal approach combining ion-exchange membranes and flowable particle electrodes, has been actively explored over the past seven years, driven by the possibility of energy-efficient, sustainable, and fully continuous production of high-quality fresh water, as well as flexible management of the particle electrodes and concentrate stream. Here, we provide a comprehensive overview of current advances of this interesting technology with particular attention given to FCDI principles, designs (including cell architecture and electrode and separator options), operational modes (including approaches to management of the flowable electrodes), characterizations and modeling, and environmental applications (including water desalination, resource recovery, and contaminant abatement). Furthermore, we introduce the definitions and performance metrics that should be used so that fair assessments and comparisons can be made between different systems and separation conditions. We then highlight the most pressing challenges (i.e., operation and capital cost, scale-up, and commercialization) in the full-scale application of this technology. We conclude this state-of-the-art review by considering the overall outlook of the technology and discussing areas requiring particular attention in the future.
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Affiliation(s)
- Changyong Zhang
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Jinxing Ma
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Lei Wu
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Jingyi Sun
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Li Wang
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520, United States
| | - Tianyu Li
- Beijing Origin Water Membrane Technology Company Limited, Huairou, Beijing 101400, P. R. China
| | - T David Waite
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
- Shanghai Institute of Pollution Control and Ecological Safety, Tongji University, Shanghai 200092, P. R. China
- UNSW Centre for Transformational Environmental Technologies, Yixing, Jiangsu Province 214206, P. R. China
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Zhang C, Cheng X, Wang M, Ma J, Collins R, Kinsela A, Zhang Y, Waite TD. Phosphate recovery as vivianite using a flow-electrode capacitive desalination (FCDI) and fluidized bed crystallization (FBC) coupled system. WATER RESEARCH 2021; 194:116939. [PMID: 33640752 DOI: 10.1016/j.watres.2021.116939] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 01/29/2021] [Accepted: 02/15/2021] [Indexed: 06/12/2023]
Abstract
It is critical to both effectively remove and recover phosphate (P) from wastewater given the wide-ranging environmental (i.e., preventing eutrophication and restoring water quality) and economic (i.e., overcoming P resource scarcity) benefits. More recently, considerable academic effort has been devoted towards harvesting P as vivianite, which can be used as a potential slow-release fertilizer and possible reagent for the manufacture of lithium iron phosphate (LiFePO4), the precursor in fabricating Li-ion secondary batteries. In this study, we propose an innovative P recovery process, in which P is first preconcentrated via a flow-electrode capacitive deionization (FCDI) device followed by immobilization as vivianite crystals in a fluidized bed crystallization (FBC) column. The effects of different operational parameters on FCDI P preconcentration performance and energy consumption are investigated. Results show that 63% of P can be removed and concentrated in the flow-electrode chamber with a reasonable energy requirement under optimal operating conditions. The FBC system resulted in immobilization of ~80% of P as triangular or quadrangular pellets, which were verified to be high-purity vivianite crystals by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) and extended X-ray absorption fine structure (EXAFS) spectroscopy. This study provides a pathway for efficient recovery of P as a value-added product (i.e., vivianite) from P-rich wastewaters.
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Affiliation(s)
- Changyong Zhang
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Xiang Cheng
- Beijing Key Laboratory for Source Control Technology of Water Pollution, Beijing Forestry University, Beijing 100083, China.
| | - Min Wang
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Jinxing Ma
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Richard Collins
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Andrew Kinsela
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Ying Zhang
- Beijing Origin Water Membrane Technology Company Limited, Huairou, Beijing, 101400, P. R. China.
| | - T David Waite
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia; UNSW Centre for Transformational Environmental Technologies, Yixing, Jiangsu Province 214206, P. R. China.
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Honarparvar S, Zhang X, Chen T, Alborzi A, Afroz K, Reible D. Frontiers of Membrane Desalination Processes for Brackish Water Treatment: A Review. MEMBRANES 2021; 11:246. [PMID: 33805438 PMCID: PMC8066301 DOI: 10.3390/membranes11040246] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/19/2021] [Accepted: 03/23/2021] [Indexed: 12/31/2022]
Abstract
Climate change, population growth, and increased industrial activities are exacerbating freshwater scarcity and leading to increased interest in desalination of saline water. Brackish water is an attractive alternative to freshwater due to its low salinity and widespread availability in many water-scarce areas. However, partial or total desalination of brackish water is essential to reach the water quality requirements for a variety of applications. Selection of appropriate technology requires knowledge and understanding of the operational principles, capabilities, and limitations of the available desalination processes. Proper combination of feedwater technology improves the energy efficiency of desalination. In this article, we focus on pressure-driven and electro-driven membrane desalination processes. We review the principles, as well as challenges and recent improvements for reverse osmosis (RO), nanofiltration (NF), electrodialysis (ED), and membrane capacitive deionization (MCDI). RO is the dominant membrane process for large-scale desalination of brackish water with higher salinity, while ED and MCDI are energy-efficient for lower salinity ranges. Selective removal of multivalent components makes NF an excellent option for water softening. Brackish water desalination with membrane processes faces a series of challenges. Membrane fouling and scaling are the common issues associated with these processes, resulting in a reduction in their water recovery and energy efficiency. To overcome such adverse effects, many efforts have been dedicated toward development of pre-treatment steps, surface modification of membranes, use of anti-scalant, and modification of operational conditions. However, the effectiveness of these approaches depends on the fouling propensity of the feed water. In addition to the fouling and scaling, each process may face other challenges depending on their state of development and maturity. This review provides recent advances in the material, architecture, and operation of these processes that can assist in the selection and design of technologies for particular applications. The active research directions to improve the performance of these processes are also identified. The review shows that technologies that are tunable and particularly efficient for partial desalination such as ED and MCDI are increasingly competitive with traditional RO processes. Development of cost-effective ion exchange membranes with high chemical and mechanical stability can further improve the economy of desalination with electro-membrane processes and advance their future applications.
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Affiliation(s)
- Soraya Honarparvar
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, USA; (S.H.); (X.Z.); (T.C.); (K.A.)
| | - Xin Zhang
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, USA; (S.H.); (X.Z.); (T.C.); (K.A.)
| | - Tianyu Chen
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, USA; (S.H.); (X.Z.); (T.C.); (K.A.)
| | - Ashkan Alborzi
- Department of Civil, Environmental and Construction Engineering, Texas Tech University, Lubbock, TX 79409, USA;
| | - Khurshida Afroz
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, USA; (S.H.); (X.Z.); (T.C.); (K.A.)
| | - Danny Reible
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409, USA; (S.H.); (X.Z.); (T.C.); (K.A.)
- Department of Civil, Environmental and Construction Engineering, Texas Tech University, Lubbock, TX 79409, USA;
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Theoretical Analysis of Constant Voltage Mode Membrane Capacitive Deionization for Water Softening. MEMBRANES 2021; 11:membranes11040231. [PMID: 33805237 PMCID: PMC8064386 DOI: 10.3390/membranes11040231] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 03/19/2021] [Accepted: 03/20/2021] [Indexed: 12/05/2022]
Abstract
Water softening is desirable to reduce scaling in water infrastructure and to meet industrial water quality needs and consumer preferences. Membrane capacitive deionization (MCDI) can preferentially adsorb divalent ions including calcium and magnesium and thus may be an attractive water softening technology. In this work, a process model incorporating ion exclusion effects was applied to investigate water softening performance including ion selectivity, ion removal efficiency and energy consumption in a constant voltage (CV) mode MCDI. Trade-offs between the simulated Ca2+ selectivity and Ca2+ removal efficiency under varying applied voltage and varying initial concentration ratio of Na+ to Ca2+ were observed. A cut-off CV mode, which was operated to maximize Ca2+ removal efficiency per cycle, was found to lead to a specific energy consumption (SEC) of 0.061 kWh/mole removed Ca2+ for partially softening industrial water and 0.077 kWh/m3 removed Ca2+ for slightly softening tap water at a water recovery of 0.5. This is an order of magnitude less than reported values for other softening techniques. MCDI should be explored more fully as an energy efficient means of water softening.
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Shang X, Hu B, Nie P, Shi W, Hussain T, Liu J. LiNi0.5Mn1.5O4-based hybrid capacitive deionization for highly selective adsorption of lithium from brine. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2020.118009] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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43
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Xu L, Mao Y, Zong Y, Wu D. Scale-up desalination: Membrane-current collector assembly in flow-electrode capacitive deionization system. WATER RESEARCH 2021; 190:116782. [PMID: 33387952 DOI: 10.1016/j.watres.2020.116782] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 12/20/2020] [Accepted: 12/22/2020] [Indexed: 06/12/2023]
Abstract
Salt removal from seawater/wastewater using flow-electrode capacitive deionization (FCDI) is of particular interest, but scale-up desalination is limited by low water production, high energy consumption and complex cell configuration. In this study, an innovative FCDI system is described that uses integrated desalination modules equipped with membrane-current collector (MCC) assembly, and thereby named as MCC-FCDI system. A single desalination module design provides an average salt removal rate (ASRR, 0.3 - 0.44 µmol/(cm2·min)) close to that of the classic FCDI system (with a graphite current collector design), but the design requires a much lower infrastructure investment, device size and energy cost. More importantly, our design enables simultaneous operation of multiple modules in the shared flow-electrode tank, easily realizing scale-up desalination. Evidence is provided by the results of the multi-module operation: multi-modules isolated closed-cycle (MICC) and multi-modules short-circuited closed-cycle (MSCC). For instance, the MICC configuration showing nearly twice the desalination performance over ~ 50 h of operation compared to that of the single ICC operation. The results indicated that in addition to making the device suitable for practical application, the Ti-mesh MCC with a woven network enables the flow electrode to achieve substantial ion adsorption capacity due to the efficient update of fresh carbon particles. In short, the results of this study showed that MCC-FCDI is a promising desalination system for scale-up applications, providing a new reference and guidance for device design.
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Affiliation(s)
- Longqian Xu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China.
| | - Yunfeng Mao
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China.
| | - Yang Zong
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China.
| | - Deli Wu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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Zhang C, Wang M, Xiao W, Ma J, Sun J, Mo H, Waite TD. Phosphate selective recovery by magnetic iron oxide impregnated carbon flow-electrode capacitive deionization (FCDI). WATER RESEARCH 2021; 189:116653. [PMID: 33232816 DOI: 10.1016/j.watres.2020.116653] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 10/08/2020] [Accepted: 11/16/2020] [Indexed: 06/11/2023]
Abstract
The recovery of phosphorus (P) from wastewaters is a worthy goal considering the potential environmental and economic benefits. Flow-electrode capacitive deionization (FCDI), which employs flowable carbon electrodes instead of the static electrodes used in conventional CDI, has been demonstrated to be a promising P recovery technology. FCDI outperforms CDI and other competitive technologies in a number of aspects including (i) large salt adsorption capacity and (ii) extremely high water recovery rate. In this study, magnetic (Fe3O4 impregnated) activated carbon particles were prepared and applied as FCDI electrodes. The magnetic carbon electrodes were found to have a strong affinity towards P, facilitating the selective adsorption of P to the magnetic particles through a ligand exhange mechanism. Continuous operation of the FCDI system could be achieved with only three minutes required to separate the electrode particles from the brine stream on application of an external magnetic field. A P-rich stream was produced on regeneration of the exhausted magnetic electrodes using alkali solution. We envision that the use of magnetic carbon enhanced flow-electrodes will pave the way for efficient operation of FCDI as well as the preferential recovery of P.
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Affiliation(s)
- Changyong Zhang
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Min Wang
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Wei Xiao
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Jinxing Ma
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Jingyi Sun
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Hengliang Mo
- Beijing Origin Water Membrane Technology Company Limited, Huairou, Beijing, 101400, P. R. China
| | - T David Waite
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia; Shanghai Institute of Pollution Control and Ecological Safety, Tongji University, Shanghai 200092, P. R. China; UNSW Centre for Transformational Environmental Technologies, Yixing, Jiangsu Province 214206, P. R. China.
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45
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Xu L, Yu C, Mao Y, Zong Y, Zhang B, Chu H, Wu D. Can flow-electrode capacitive deionization become a new in-situ soil remediation technology for heavy metal removal? JOURNAL OF HAZARDOUS MATERIALS 2021; 402:123568. [PMID: 32763769 DOI: 10.1016/j.jhazmat.2020.123568] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 07/04/2020] [Accepted: 07/21/2020] [Indexed: 06/11/2023]
Abstract
In this study, we present a novel soil electrochemical remediation technology (called S-FCDI), which is based on flow-electrode capacitive deionization (FCDI), for Cd removal from kaolin while under continuous operation mode. The results demonstrated that Cd can be effectively removed from kaolin with reasonable energy consumption and minimal macroelement loss. The carboxylic (OOH) functional groups on the surface of activated carbon (AC) facilitated the transfer of Cd from kaolin onto carbon surface. A stable acidic environment, which is advantageous for continuous Cd desorption, was achieved as a result of the balance between H+ generation and transmembrane migration. Once these net negative charges on the particle were eliminated or reversed, the adsorbed Cd could be released easily and driven in concentrated stream by electrostatic repulsion. Under the optimal operating conditions (i.e., carbon =50 g/L, j = 3.47 A/m2, pHi = 3.2, [NaCl]a =8.6 mmol/L), more than 80 % Cd was removed from (200 g) kaolin after continuous 19 h operation at a relatively low electricity consumption of 22.7 kW h/kg Cd and a limited Al loss of 0.06 wt‰. These results from this work demonstrated that S-FCDI could be an alternative soil electrochemical remediation technology for heavy metal removal with low soil damage.
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Affiliation(s)
- Longqian Xu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai, 200092, PR China.
| | - Chao Yu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai, 200092, PR China.
| | - Yunfeng Mao
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai, 200092, PR China.
| | - Yang Zong
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai, 200092, PR China.
| | - Bing Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai, 200092, PR China.
| | - Huaqiang Chu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai, 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.
| | - Deli Wu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai, 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.
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Ashrafizadeh SN, Ganjizade A, Navapour A. A brief review on the recent achievements in flow-electrode capacitive deionization. KOREAN J CHEM ENG 2021. [DOI: 10.1007/s11814-020-0677-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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47
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Xu L, Xie Y, Zong Y, Mao Y, Zhang B, Chu H, Wu D. Formic acid recovery from EDTA wastewater using coupled ozonation and flow-electrode capacitive deionization (Ozo/FCDI): Performance assessment at high cell voltage. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2020.117613] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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48
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Highly efficient water softening by mordenite modified cathode in asymmetric capacitive deionization. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.117240] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Lin L, Hu J, Liu J, He X, Li B, Li XY. Selective Ammonium Removal from Synthetic Wastewater by Flow-Electrode Capacitive Deionization Using a Novel K 2Ti 2O 5-Activated Carbon Mixture Electrode. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:12723-12731. [PMID: 32926784 DOI: 10.1021/acs.est.0c04383] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Ammonium (NH4+) in wastewater is both a major pollutant and a valuable resource. Flow-electrode capacitive deionization (FCDI) is a promising technology for chemical-free and environmentally friendly NH4+ removal and recovery from wastewater. However, the coexisting sodium (Na+) in wastewater, with a similar hydrated radius to NH4+, competes for the adsorption sites, resulting in low NH4+ removal efficiency. Here, potassium dititanate (K2Ti2O5 or KTO) particles prepared by the electrospray method followed by calcination were mixed with activated carbon (AC) powder to form a novel KTO-AC flow-electrode for selective NH4+ removal over Na+. The mixed KTO-AC electrode exhibits a much higher specific gravimetric capacitance in NH4Cl solution than in NaCl solution. Compared with the pure AC electrode in the FCDI tests on NH4+ removal from synthetic wastewater, 25 wt % KTO addition in the electrode mixture increases the adsorption selectivity from 2.3 to 31 toward NH4+ over Na+, improves the NH4+ removal from 28.5% to 64.8% and increases the NH4+ desorption efficiency from 35.6% to over 80%, achieving selective NH4+ recovery and effective electrode regeneration. Based on DFT calculations, NH4+ adsorption on the K2Ti2O5 (0 0 1) surface is more thermodynamically favorable than that of Na+, which contributes to the high NH4+ adsorption selectivity observed.
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Affiliation(s)
- Lin Lin
- Environmental Science and New Energy Technology Research Center, Tsinghua-Berkeley Shenzhen Institute, Tsinghua University, Shenzhen 518055, China
| | - Jiahui Hu
- Shenzhen Engineering Research Laboratory for Sludge and Food Waste Treatment and Resource Recovery, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, China
| | - Jiahua Liu
- Environmental Science and New Energy Technology Research Center, Tsinghua-Berkeley Shenzhen Institute, Tsinghua University, Shenzhen 518055, China
| | - Xin He
- Environmental Science and New Energy Technology Research Center, Tsinghua-Berkeley Shenzhen Institute, Tsinghua University, Shenzhen 518055, China
| | - Bing Li
- Shenzhen Engineering Research Laboratory for Sludge and Food Waste Treatment and Resource Recovery, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, China
| | - Xiao-Yan Li
- Environmental Science and New Energy Technology Research Center, Tsinghua-Berkeley Shenzhen Institute, Tsinghua University, Shenzhen 518055, China
- Shenzhen Engineering Research Laboratory for Sludge and Food Waste Treatment and Resource Recovery, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, China
- Environmental Engineering Research Centre, Department of Civil Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China
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50
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Liu E, Lee LY, Ong SL, Ng HY. Treatment of industrial brine using capacitive deionization (CDI) towards zero liquid discharge - challenges and optimization. WATER RESEARCH 2020; 183:116059. [PMID: 32721705 DOI: 10.1016/j.watres.2020.116059] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 06/05/2020] [Accepted: 06/13/2020] [Indexed: 06/11/2023]
Abstract
Thermal-based Zero Liquid Discharge (ZLD) process has been used for managing industrial brine. However, conventional thermal ZLD process is very energy intensive. In view of this, pre-concentration techniques have been applied prior to thermal process to reduce energy consumption of ZLD systems. Capacitive Deionization (CDI) is an emerging desalination technique and has yet to be extensively explored for the treatment of industrial brine especially for ZLD applications. High concentration of total dissolved solids (TDS) and high fouling potential of industrial brine are two major challenges in CDI process. This paper reviews the possible factors for optimizing CDI process in industrial brine treatment, namely, cell architectures, strategies in operation and fouling control. Cell architectures of membrane CDI (MCDI) and flow-electrode CDI (CDI) are preferred options for treating industrial brine compared with classic CDI in terms of energy consumption and fouling propensity. There are other operational strategies that could enhance the feasibility of using CDI process for ZLD application. These include reversed voltage desorption, multi-stage operation, brine recirculation and fouling control. Fouling control methods comprise pretreatment, antifouling modification, antiscalant and chemical cleaning. These methods could be integrated to optimize fouling mitigation. In addition to providing insights on feasibility of using CDI to concentrate industrial brines, this review also proposed guidelines for optimizing CDI process applied to treat industrial brines for ZLD applications.
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Affiliation(s)
- Enyu Liu
- Centre for Water Research, Department of Civil & Environmental Engineering, Faculty of Engineering, National University of Singapore, S 117576, Singapore.
| | - Lai Yoke Lee
- NUS Environmental Research Institute, National University of Singapore, S 117411, Singapore.
| | - Say Leong Ong
- Centre for Water Research, Department of Civil & Environmental Engineering, Faculty of Engineering, National University of Singapore, S 117576, Singapore; NUS Environmental Research Institute, National University of Singapore, S 117411, Singapore.
| | - How Yong Ng
- Centre for Water Research, Department of Civil & Environmental Engineering, Faculty of Engineering, National University of Singapore, S 117576, Singapore; NUS Environmental Research Institute, National University of Singapore, S 117411, Singapore.
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