Capacitive deionization: a promising technology for water defluoridation: a review

Abstract Capacitive deionization (CDI) is among the promising technologies employed for water purification. CDI has been studied for the removal of various ionic species from water including fluoride ion (F−) with promising results. However, there is no comprehensive literature that summarizes the use of CDI for water defluoridation applications. Therefore, this review paper critically analyzes different electrode materials that have been studied for water defluoridation, their electrosorption capacities and F− removal efficiencies. It further discussed the parameters that influence CDI efficiency during defluoridation and point out the issues of F− selectivity when coexisting with other ions in the solution. We can conclude that different electrode materials have shown different abilities in electrosorption of F−. The carbon-based materials possess high surface area and good electrical conductivity which is paramount for ion adsorption but lack selectivity for F− removal. Metal oxides and hydroxides have been reported with improved electrosorption capacity and high selectivity to F− due to the ion exchange between the F− and the hydroxyls surface of the metal oxides/hydroxides. Apart from the good performance of these materials for defluoridation, the discovery of actual practicability use of the electrode materials for defluoridation for commercial scale is still a need.

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Removal of lead ions from water by capacitive deionization electrode materials derived from chicken feathers

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2019.074 ◽

2019 ◽

Vol 9 (3) ◽

pp. 282-291 ◽

Cited By ~ 4

Author(s):

T. Alfredy ◽

Y. A. C. Jande ◽

T. Pogrebnaya

Keyword(s):

Electrode Materials ◽

High Surface ◽

High Surface Area ◽

Koh Activation ◽

Capacitive Deionization ◽

Activation Temperature ◽

Variable Parameters ◽

Chicken Feathers ◽

Bet Method ◽

Removal Of Heavy Metals

Abstract Capacitive deionization (CDI) is a promising and rapidly growing technology for water treatment and the electrode materials play a key role in improving CDI performance. In this study, high surface area activated carbon was prepared from chicken feather (CF) bio-waste through pyrolysis and KOH activation; the KOH:CF ratio (R) and activation temperature (Ta) were variable parameters. The material was characterized by using the Brunauer, Emmett and Teller (BET) method, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The lead (Pb2+) removal test was performed with a CDI cell containing the fabricated carbon electrode and 100 mg L−1 Pb(NO3)2 solution; the sample prepared with the ratio R of 1:1 and Ta = 800 °C exhibited higher Pb2+ removal efficiency of 81% and electro sorption capacity of 4.1 mg g−1 at the electrode potential 1.2 V and flow rate 5 mL min−1. Therefore, CF-derived carbon is considered as a promising CDI electrode material for removal of heavy metals from waste water.

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Carbon-Based Electric Double Layer Capacitors for Water Desalination

ASME 2010 8th International Conference on Nanochannels, Microchannels, and Minichannels: Parts A and B ◽

10.1115/fedsm-icnmm2010-30696 ◽

2010 ◽

Author(s):

Batya A. Fellman ◽

Muataz Atieh ◽

Evelyn N. Wang

Keyword(s):

Electrode Materials ◽

Salt Water ◽

High Surface ◽

High Surface Area ◽

Water Desalination ◽

Electrode Geometry ◽

Capacitive Deionization ◽

Water Stream ◽

Carbon Based Nanomaterials ◽

Carbon Based

In capacitive deionization (CDI), salt water is passed through two polarized electrodes, whereby the salt is adsorbed onto the electrode surface and removed from the water stream. This approach has received renewed interest for water desalination due to the development of new high-surface area carbon-based nanomaterials. However, there is currently limited understanding as to how electrode geometry, surface properties, and capacitance affect ion capture. In this work, we experimentally investigate various standard carbon-based electrode materials, including activated carbon and carbon cloths, as well as microfabricated silicon structures for CDI. Electrochemical characterization through cyclic voltammetry was used to determine the electrochemical properties of each material. In addition, a mini-channel test cell was fabricated to perform parametric studies on ion capture. By controlling electrode geometry and chemistry in these studies, the work helps elucidate transport mechanisms and provide insight into the design of optimal materials for capacitive deionization.

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Synthesis, properties, and performance of nanostructured metal oxides for supercapacitors

Pure and Applied Chemistry ◽

10.1515/pac-2013-1021 ◽

2014 ◽

Vol 86 (5) ◽

pp. 611-632 ◽

Cited By ~ 19

Author(s):

Deepak P. Dubal ◽

Rudolf Holze

Keyword(s):

Metal Oxides ◽

Double Layer ◽

Electrode Materials ◽

High Surface ◽

High Surface Area ◽

Synthesis Properties ◽

And Performance ◽

Nanostructured Metal Oxides ◽

Power Capability ◽

Nanostructured Metal

AbstractBeyond activated carbon and other forms of high-surface area carbon operating solely as double layer storage materials in capacitors of high capacitance commonly somewhat imprecisely called supercapacitors other electrode materials storing electric charge by reversible and fast superficial redox processes are studied as active masses. The resulting devices combining double layer and Faradaic process-based charge storage – commonly called hybrid ones – show significantly higher capacitances at only marginally diminished power capability. Among the suggested materials metal oxides feature most prominently. Their formation, characterization and properties together with the performance of prepared devices are reviewed here.

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Single and Dual Metal Oxides as Promising Supports for Carbon Monoxide Removal from an Actual Syngas: The Crucial Role of Support on the Selectivity of the Au–Cu System

Catalysts ◽

10.3390/catal9100852 ◽

2019 ◽

Vol 9 (10) ◽

pp. 852 ◽

Cited By ~ 5

Author(s):

Bernay Cifuentes ◽

Felipe Bustamante ◽

Martha Cobo

Keyword(s):

Metal Oxides ◽

High Surface ◽

High Surface Area ◽

Carbon Deposits ◽

Promising Strategy ◽

Cu Catalysts ◽

Dual Metal ◽

Effect Of The Support ◽

Lower Capacity

A catalytic screening was performed to determine the effect of the support on the performance of an Au–Cu based system for the removal of CO from an actual syngas. First, a syngas was obtained from reforming of ethanol. Then, the reformer outlet was connected to a second reactor, where Au–Cu catalysts supported on several single and dual metal oxides (i.e., CeO2, SiO2, ZrO2, Al2O3, La2O3, Fe2O3, CeO2-SiO2, CeO2-ZrO2, and CeO2-Al2O3) were evaluated. AuCu/CeO2 was the most active catalyst due to an elevated oxygen mobility over the surface, promoting CO2 formation from adsorption of C–O* and OH− intermediates on Au0 and CuO species. However, its lower capacity to release the surface oxygen contributes to the generation of stable carbon deposits, which lead to its rapid deactivation. On the other hand, AuCu/CeO2-SiO2 was more stable due to its high surface area and lower formation of formate and carbonate intermediates, mitigating carbon deposits. Therefore, use of dual supports could be a promising strategy to overcome the low stability of AuCu/CeO2. The results of this research are a contribution to integrated production and purification of H2 in a compact system.

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Heteroatom-enhanced the Formation of Mesoporous Carbon Microspheres with High Surface Area as Supercapacitor Electrode Materials

International Journal of Electrochemical Science ◽

10.20964/2017.11.55 ◽

2017 ◽

pp. 10687-10700 ◽

Cited By ~ 3

Author(s):

Zhuan Gao ◽

Keyword(s):

Surface Area ◽

Mesoporous Carbon ◽

Electrode Materials ◽

High Surface ◽

High Surface Area ◽

Carbon Microspheres ◽

Supercapacitor Electrode ◽

Supercapacitor Electrode Materials

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High surface area metal oxides from matrix assisted preparation in activated carbons

Studies in Surface Science and Catalysis - Scientific Bases for the Preparation of Heterogeneous Catalysts - Proceedings of the 8th International Symposium, Louvain-la-Neuve, Belgium 9-12, 2002 ◽

10.1016/s0167-2991(00)80646-1 ◽

2000 ◽

pp. 93-100 ◽

Cited By ~ 17

Author(s):

M. Schwickardi ◽

T. Johann ◽

W. Schmidt ◽

O. Busch ◽

F. Schüth

Keyword(s):

Metal Oxides ◽

Surface Area ◽

Activated Carbons ◽

High Surface ◽

High Surface Area

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Rich N/O/S co-doped porous carbon with a high surface area from silkworm cocoons for superior supercapacitors

New Journal of Chemistry ◽

10.1039/c9nj04195h ◽

2019 ◽

Vol 43 (48) ◽

pp. 19372-19378 ◽

Cited By ~ 1

Author(s):

Jianyu Huang ◽

Simin Liu ◽

Zifang Peng ◽

Zhuoxian Shao ◽

Yuanyuan Zhang ◽

...

Keyword(s):

Surface Area ◽

Porous Carbon ◽

Electrode Materials ◽

Synergistic Effects ◽

High Surface ◽

High Surface Area ◽

Porous Carbons ◽

Co Doped

The synergistic effects of high surface area and abundant heteroatoms make porous carbons superior electrode materials.

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Synthesis of Hierarchical Graphene-MnO2 Nanowire Composites with Enhanced Specific Capacitance

Asian Journal of Chemistry ◽

10.14233/ajchem.2019.21924 ◽

2019 ◽

Vol 31 (8) ◽

pp. 1709-1718

Author(s):

T. Veldevi ◽

K. Thileep Kumar ◽

R.A. Kalaivani ◽

S. Raghu ◽

A.M. Shanmugharaj

Keyword(s):

Surface Area ◽

Electrode Materials ◽

High Surface ◽

Specific Capacity ◽

High Surface Area ◽

Rate Capability ◽

Sulfate Solution ◽

High Rate ◽

Chemical Compositions ◽

Structure Morphology

Hierarchical nanostructured graphene–manganese dioxide nanowire (G-MnO2-NW) composites have been prepared by hydrothermal synthesis route using water/1-decanol as the medium. Synthesized materials were analyzed using various characterization tools to corroborate their chemical compositions, structure/morphology and surface area. Electrochemical measurements of the synthesized G-MnO2-NW electrode materials delivered the highest specific capacity (255 Fg-1), high rate capability and improved cycling stability at 0.5 Ag–1 in 1M sodium sulfate solution and this fact may be attributed to its high surface area and porosity. Moreover, synthesized G-MnO2-NW electrodes displayed better energy and power density, when compared to the MnO2-NW based electrodes.

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Enhanced capacitive deionization performance by an rGO–SnO2 nanocomposite modified carbon felt electrode

RSC Advances ◽

10.1039/c7ra12764b ◽

2018 ◽

Vol 8 (8) ◽

pp. 4182-4190 ◽

Cited By ~ 15

Author(s):

Syed Kamran Sami ◽

Jung Yong Seo ◽

Suh-Eun Hyeon ◽

Md. Selim Arif Shershah ◽

Pil-Jin Yoo ◽

...

Keyword(s):

Surface Area ◽

High Surface ◽

High Surface Area ◽

Capacitive Deionization ◽

Carbon Felt ◽

Nano Composite ◽

Carbon Felt Electrode

The rGO–SnO2 nano-composite with a significantly high-surface-area, greatly improves the electrosorption capacity and is proposed as a novel electrode for capacitive deionization applications.

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