Keywords capacitive deionization desalination electrosorption nanoporous carbon aerogel introduction in recent years, one of the most critical problems affecting people. For water quality greater than 1 megohmcm, where large volumes of water are required, an sdi system typically includes a. As a promising desalination technology, capacitive deionization cdi have shown practicality and costeffectiveness in brackish water. Carbon aerogel is a material that enables the successful purification of water because of its high surface area, optimum pore size, and low electrical resistivity. Capacitive deionization cdi methodthe basic concepts salty water flows by or through a pair of high surface porous electrodes. Pdf water desalination via capacitive deionization. This direct current low voltage can easily be produced using a small solar panel. Capacitive deionization cdi is a novel technology that has been successfully utilized for many water treatmentpurification applications. Capacitive deionization based water desalination system. A novel and general method is proposed to construct three. Keywords capacitive deionization desalination electrosorption nanoporous carbon aerogel introduction in recent years, one of the most critical problems affecting people throughout the world is the lack of clean, fresh water. Technology of water desalination by capacitive deionization. Characterization of resistances of a capacitive deionization. Commons is a freely licensed media file repository.
Capacitive deionization cdi has emerged as a promising way to obtain freshwater from saline water, but its implementation is in its infancy and remains challenging due to the low salt adsorption. The new capacitive deionization system cdi removes ions, contaminants impurities from water and other aqueous process streams, and further selectively places the removed ions back into solution during regeneration. Water recovery rate in shortcircuited closedcycle operation. The capacitive deionization cdi process is a technology employed to remove ionic materials using an electrostatic adsorption reaction on the electric double layer edl created on the electrode surface interface when a potential is applied on the electrode. Salt rejection in flowbetween capacitive deionization devices. Logan department of civil and environmental engineering, the pennsylvania state university, university park, pennsylvania 16802, united.
However at the time when this research was started in 1998, the technology was only at. However, the ion removal capacity of cdi systems is not sufficient for desalting highconcentration saline water. Page 1 r advances in capacitive deionization using reticle carbon reticle inc. During the application of potential difference between the electrodes, positively charged species are electroadsorbed onto the negatively polarized electrode in the double layer region and the contrary. Capacitive deionization system unt digital library. Capacitive deionization for water desalination aubrey mccutchan, freshman research scholar department of civil and environmental engineering with dr.
Our reliable sdi systems consist of activated carbon and ion exchange. Information from its description page there is shown below. Advances in capacitive deionization using reticle carbon. Capacitive deionization cdi is a water desalination technique in which salt ions are removed from brackish water by flowing through a spacer channel with porous electrodes on each side.
Michael stadermann of llnl clean water and renewable energy are two of the most important engineering challenges of this century, and the two problems are intimately coupled. Capacitive deionization cdi is a desalination technology utilizing electrosorption and desorption of ionic salts. However, the commonly used carbon electrode materials suffer from such issues as unsuitable porous structures, low conductivity and poor wettability, which limit th nanomaterial applications in water. You may do so in any reasonable manner, but not in.
Asymmetric configuration of pseudocapacitive composite and rgo. In many cases, the cdi technology has shown increased. Membrane capacitive deionization capdi in volteas patented membrane capacitive deionization technology capdi, ions are removed from the feed water by applying an electrical potential difference between two electrodes covered with selective ion exchange membranes. During cdi, ions are adsorbed onto the surface of porous electrodes by applying a. Likewise, cations positive charge are stored in the cathode, which is the negatively polarized electrode. Santiago a, a department of mechanical engineering, stanford university, stanford, ca 94305, united states b lawrence livermore national laboratory, 7000 east avenue, livermore, ca 94550, united states article info article history. In cdi, brackish water is pumped through an electrical. Anions, ions with a negative charge, are removed from the water and are stored in the positively polarized electrode. Aug 20, 20 a novel and general method is proposed to construct three. Santiago, and michael stadermann, department of mechanical engineering, stanford university stanford, 440 escondido mall, stanford, california 94305, united states. Development of a predictive and mechanistic model for capacitive deionization by amy heldenbrand the objective of this research was to develop a mechanistic and predictive model for capacitive deionization cdi. The interplay between the micro and macroscale transport mechanisms in the porous electrodes. However at the time when this research was started in 1998, the technology was only at the laboratory scale level. Capacitive deionization of seawater unt digital library.
Among which, capacitive deionization cdi has emerged as a novel cost effective and environment friendly desalination technology. The components for your sdi system will be selected based on your feedwater quality, flow rate and product water quality requirements. Preparation and application of electrodes in capacitive deionization. John veenstra abstract potable water is a resource essential to human activity and is becoming increasingly difficult to attain as human demand for it grows. Capacitive deionization using activated carbon super capacitor for water desalination contact. Desalination and contaminant removal from water by capacitive. The key difference between mcdi technology and standard capacitive deionization cdi technolo. Upon applying a small voltage difference between the two electrodes, cations move to and are accumulated in electrostatic double layers inside the negatively charged cathode and the anions are. Polyoxometalate based binder free capacitive deionization. List of capacitive deionization companies, manufacturers and suppliers. Capacitive deionization enables lower energy use and selectivity cdi removes salt from water using charged electrodes r ratio of target ion concentration to matrix ion. The private files comparison of energy consumption in desalination by capacitive deionization and reverse osmosis you are trying to view is password protected. Energetic performance optimization of a capacitive deionization system operating with transient cycles and brackish water onur n. Energetic performance optimization of a capacitive.
Capacitive deionization cdi is an alternative water purification technology. Capacitive deionization cdi offers a good solution for small scale and distributed inland applications technical innovation cdi use a low applied voltage to pull the ions out of solution operates a low pressure creates a low volume of concentrate improved waste management. Carbon aerogel is a material that enables the successful purification of water because of its high surface area. Santiago a, a department of mechanical engineering, stanford university, stanford, ca 94305, united states. Mcdi uses capacitive electrodes and ionexchange ix membranes to remove ions such as chloride and calcium from various water sources, including, tap, well, and even seawater 49. Desalination of brackish water using capacitive deionization. Pdf capacitive deionization cdi is a novel technology that has been successfully utilized for many water treatmentpurification applications. Welldesigned cdi cells are a promising alternative to current desalination technologies, including reverse osmosis. Capacitive deionization cdi is a technology to deionize water by applying an electrical potential difference over two electrodes. Files are available under licenses specified on their description. This file is licensed under the creative commons attributionshare alike 3. Novel and emerging technologies for produced water.
Ion selectivity in capacitive deionization with functionalized electrode. Dimensional graphenemetal oxide nanoparticle hybrids. While flowelectrode cdi is a promising desalination technology that has major advantages when the electrodes are operated in the shortcircuited closedcycle scc mode, little attention has been paid to the water recovery rate, which, in the scc mode, is determined by the need for partial replacement of the saline electrolyte of the flow electrodes. Novel and emerging technologies for produced water treatment. Capacitive deionization cdi is a promising new technology for water desalination making use of an electrical voltage applied between two electrodes. Water purification through service deionization water technologies.
Aug 10, 2016 the techniques, such as electrodialysis, membrane filtration, advanced oxidation process, thermal evaporation, can be used nowadays to treat salty water. The university of texas at austin, 1 university station, c2200, austin, tx 78712, usa highlights. Files are available under licenses specified on their description page. Capacitive deionization using activated carbon super. Grouping all these methods in the technology class of cdi makes it possible to treat evolving new technologies in. Electrode materials are crucial for the deionization performance. Yasamin salamat performance improvement of capacitive. Capacitive deionization with carbon aerogel electrodes is an efficient and economical new process for removing salt and impurities from water. Protected page enter password elimelech research group.
Based on a porous carbon electrode, capacitive deionization cdi is a promising desalination technology in which ions are harvested and stored in an electrical double layer. Here we report a zerowastewater capacitive deionization cdi technology using a thiolfunctionalized graphene oxideactivated carbon goac composite material. Capacitive deionization flow electrode cdi cell during. It provides a separation process that does not utilize chemical regeneration processes, and thus significantly reduces or completely eliminates secondary wastes associated with. This work developed polyoxometalate as a new material for capacitive deionization electrode. Characterization of resistances of a capacitive deionization system yatian qu, theodore f. This page was last edited on 23 november 2016, at 10.
Capacitive deionization of saline water using graphene. For this mixed capacitive deionization electrode, its excellent sea water desalination performance originates from the synergistic effect between siw 12 o 40 4. Join our growing community of environmental professionals who are currently subscribed to weekly newsletters, product alerts, job alerts, and our monthly event updates and article newsletters. About cdi capacitive deionization and electrosorption. Development of a predictive and mechanistic model for. Hybrid capacitive deionization to enhance the desalination. Capacitive deionization enables lower energy use and selectivity cdi removes salt from water using charged electrodes r ratio of target ion concentration to matrix ion concentration in feed stream impact of selectivity on total removalenergy. Capacitive deionization cdi is a promising desalination technology, which operates at low pressure, low temperature, requires little infrastructure, and has the potential to consume less energy for brackish water desalination.
Us epa technical workshops for the hydraulic fracturing. The electrodes can have different chemistries and, for instance, contain intercalation host compounds, or are synthetized of porous carbon particles. Figures of merit and control methods for capacitive. Desalination and contaminant removal from water by. The performance of this electrode is well retained after 30 cycle test. The commonlyknown gouy chapman stern gcs model was modified to account for finite ion size and. Ultrahighefficiency capacitive devices for continuous water. Capacitive deionization technology cdt is a lowpressure nonmembrane desalination process, with the potential to be a power tool in the desalination toolbox of the future farmer5 et al. Energy consumption in batchmode capacitive deionization. Capacitive deionization cdi is a technology to deionize water by applying an electrical potential difference over two electrodes, which are often made of porous carbon. During cdi, ions are adsorbed onto the surface of porous electrodes by applying a low voltage 1. A parametric study of multiscale transport phenomena and. Application of capacitive deionization technology to the. Figures of merit and control methods for capacitive deionization cdi ali hemmatifar and juan g.
Carbon materials are the main components of electrodes in cdi, while addition of organic and inorganic materials with carbon materials enhances the desalination performance. The commonlyknown gouy chapman stern gcs model was. Over the past decade, capacitive deionization cdi has realized a surge in attention in the field of water desalination and can now be considered as an important technology class, along with. Review on carbonbased electrode materials for application. Jul 18, 2017 over the past decade, capacitive deionization cdi has realized a surge in attention in the field of water desalination and can now be considered as an important technology class, along with. The common cdi cells employ a symmetric electrode pair configuration. Review on carbonbased electrode materials for application in. Low energy desalination using battery electrode deionization taeyoung kim, christopher a. Capacitive deionization flow electrode cdi cell during adsorption. For the first time, it is demonstrated that this graphene.
Fabrication of a carbon electrode using activated carbon. This is particularly true for the desalting of water with low to moderate levels of salinity brackish water, where cdi is most efficient. Desalination of brackish water using capacitive deionization cdi. Capacitive deionization cdi is a relatively novel desalination technology which uses electrically charged porous electrodes to remove ions from low salinity water streams. Capacitive deionization provides a path to low power requirement, energy efficient low maintenance modular systems that can easily be deployed in. Pdf nitrate removal and recovery by capacitive deionization. Development and evaluation of an electrode for the capacitive. The desel system capacitive deionization for the removal of ions from water leonard p. In many cases, the cdi technology has shown increased efficiency compared to the other contemporary technologies. Low energy desalination using battery electrode deionization. However, cdi devices consume significantly more energy than the theoretical thermodynamic minimum, and this is at least partly due to resistive power dissipation. All structured data from the file and property namespaces is available under the creative commons cc0 license.
Santiago, and michael stadermann, department of mechanical engineering, stanford university stanford, 440 escondido mall, stanford, california 94305, united states lawrence livermore national laboratory, 7000 east avenue, livermore, california 94550, united states. Water desalination by an electrochemical means capacitive. Capacitive deionization is a relatively new and novel desalination technique where an electric. Pdf capacitive deionization cdi is an emerging technology for the facile removal of charged ionic species from aqueous solutions, and is. The techniques, such as electrodialysis, membrane filtration, advanced oxidation process, thermal evaporation, can be used nowadays to treat salty water. Capacitive deionizationdefining a class of desalination technologies. Energy breakdown in capacitive deionization ali hemmatifar a, james w.
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