A synthesis of pcf from pmmabpan via electrospinning of pmmabpan into fibers, selfassembly of pmmabpan into disordered, bicontinuous pmma and pan domains, and pyrolysis of pmmabpan into pcf with uniform and interconnected pores in a continuous carbon matrix. Rockingchair capacitive deionization with flowthrough. Us8518229b2 integrated electrodecurrent collector sheet. The process of capacitive deionization cdi is a cost effective. Author links open overlay panel ayelet kalfa a b barak shapira a b alexey shopin a b izaak cohen a b eran avraham a b doron aurbach a. The activated carbon was used as electrodeactive material for capacitive deionization cdi. 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. Significance of the micropores electrosorption resistance in. You may do so in any reasonable manner, but not in. 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. Membranefree hybrid capacitive deionization system based on. Figures of merit and control methods for capacitive. Capacitive deionization cdi, as a promising electrochemical water treatment technology, has attracted large attention over. Information from its description page there is shown below.
Selective ion separation by capacitive deionization cdi based technologies. However, the conventional carbon electrode materials for cdi have low densities, which occupy large volumes and are disadvantageous for use in limited space e. Capacitive deionization with carbon aerogel electrodes is an efficient and economical new process for removing salt and impurities from water. An electrochemical cell for capacitive deionization and electrochemical purification and regeneration of electrodes includes two oppositely disposed, spacedapart end plates, one at each end of the cell.
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 is a technology to deionize water by applying an electrical potential difference over two electrodes, which are often made of porous carbon. View capacitive deionization research papers on academia. This direct current low voltage can easily be produced using a small solar panel. Unlike ion exchange, one of the more conventional deionization processes, no chemicals are required for regeneration. Electrochemical parameters, such as current values, charge, specific charge and charge. Unlimited viewing of the articlechapter pdf and any associated supplements and figures. However at the time when this research was started in 1998, the technology was only at the laboratory scale level. Carbon materials are the main components of electrodes in cdi, while addition of organic and inorganic materials with carbon materials enhances the desalination performance. Us5425858a method and apparatus for capacitive deionization. Capacitive deionization cdi becomes a promising desalination technology for the brackish water treatment nowadays because of the increasing demand for fresh water around the world 1,2. Capacitive deionization cdi is a competent water desalination technique offering an appropriate route to obtain clean water. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed. Capacitive deionization cdi is an emerging technique for removing dissolved, charged species from aqueous solutions, and has bee n previou sly app lied to bra ckish wa ter desa linati on.
Pdf optimal conditions for efficient flowelectrode. Simulation of capacitive deionization accounting the change of stern. Carbon nanomaterials for water desalination by capacitive. Mesoporous carbon for capacitive deionization of saline water. A capacitive deionization cdi system is one of the emerging desalination technologies used to purify the riverbrackish water. Alfredy 1 department of materials and energy science and engineering, the nelson mandela african institution of science and technology, p. Capacitive deionization of nacl solutions with modified.
Solar desalination with capacitive deionization research. Development of a predictive and mechanistic model for. Pdf capacitive deionization cdi is a novel technology that has been successfully utilized for many water. Capacitive deionization cdi is an emerging method for removal of charged ionic species from aqueous solutions, based on electrostatic interactions between mostly inorganic ions and porous carbon electrodes.
Capacitive deionization cdi is a desalination technology utilizing electrosorption and desorption of ionic salts. However, a rational designed structure of the electrode materials is essentially required for achieving high cdi performance. In this study, high surface area activated carbon was prepared from chicken feather cf biowaste through pyrolysis and koh activation. Likewise, cations positive charge are stored in the cathode, which is the negatively polarized electrode. Mesoporous carbon for capacitive deionization of saline. Asymmetric electrode configuration for enhanced membrane. Desalination, softening, selective removal, and energy efficiency.
Capacitive deionization for water desalination aubrey mccutchan, freshman research scholar department of civil and environmental engineering with dr. While many of the recently developed technologies no longer use a mechanism that follows the strict definition of the term capacitive, these methods nevertheless. Removal of lead ions from water by capacitive deionization. Two generally identical singlesided end electrodes, are arranged one at each end of the cell, adjacent to the end plates. Capacitive deionization defining a class of desalination technologies. The commonlyknown gouy chapman stern gcs model was modified to account for finite ion size and pore geometry by including the carnahanstarling cs equation of state and. Downloaded by universitat des saarlandes on 22052015 15. Objectoriented modeling of a capacitive deionization process. Likewise, cations positive charge are stored in the. Capacitive deionization cdi is a promising new technology for water desalination making use of an electrical voltage applied between two electrodes. Initial data showed that the highly porous carbon electrodes possessed airoxygen in the micropores, and the increased system pressure boosts the gases solubility in saline solution and carries them out of the cell in the effluent. Integrating a supercapacitor with capacitive deionization for direct energy recovery from the. Membranefree hybrid capacitive deionization system based.
This bulletin explains volteas patented membrane capacitive deionization technology capdi and describes other ionremoval technologies such as reverse osmosis, electrodialysis, electrodeionization and the ion exchange softening process. 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. The effects of system pressure on the performance stability of flowthrough capacitive deionization cdi cells was investigated. In capacitive deionization cdi, salt water is passed through two polarized electrodes, whereby salt is adsorbed onto the electrode surface and removed from. Preparation and application of electrodes in capacitive deionization. These results demonstrate that the resultant porous carbons are promising electrode materials for capacitive deionization. Capacitive deionization setup composed of a deionization cell, ph, o2, and conductivity sensors. However, the ion removal capacity irc of cdi is insufficient for practical application because such a capacity is limited by the available surface area of the carbon electrode for ion absorption.
It is an electrochemical technology that uses electrically charged. Capacitive deionization cdi has received wide attention as an emerging water treatment technology because of its low energy consumption, low cost, and high efficiency. Capacitive deionization of seawater unt digital library. Capacitive deionization cdi is an upcoming desalination technology being increasingly considered to be a simple and costeffective solution for brackish water, where electrosorption leads to the removal of charged species from water. 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. Templated preparation of high surface area graphene. Application of capacitive deionization technology to the removal of. Capacitive deionisation and electrosorption 2020 home. Realworld water samples typically contain a multitude of ions that must be considered apart from sodiumchloride salt. Capacitive deionization cdi is a promising technology for desalination due to its advantages of low driven energy and environmental friendliness. Capacitive deionization of saline water by using mos2. The electrodes are maintained at a potential difference of about one volt.
Active, expires 20310526 application number us12533,777 other versions. Motivated by the goal of simultaneously enhancing the desalination capacity and rate, this. Novel nitrogen doped graphene sponge with ultrahigh. Capacitive deionization cdi has emerged as a promising alternative for saline water desalination, yet the relatively slow desalination rate curtails its practical application. Us20100230277a1 capacitive deionization cell with balanced. Pdf objectoriented modeling of a capacitive deionization. Capacitive deionization of nacl and nano3 solutions with.
A pyrolysis product derived from a coaltar pitch was chemically activated using koh in a kohcarbon proportion of 5. Pressuredriven stabilization of capacitive deionization by. Application of capacitive deionization technology to the. Capacitive deionization cdi is an electrochemically controlled adsorption process using a low electrical field 0. Mc was prepared by selfassembly of a triblock copolymer with hydrogenbonded chains via a phenolic resin, such as resorcinol or phloroglucinol in acidic conditions, followed by carbonization and, in some cases, activation by koh. The commonlyknown gouy chapman stern gcs model was modified to account for finite ion size and.
A dynamic 2d model for electrosorption of ions in capacitive deionization cdi. Capacitive deionization cdi is a rapidly growing research field, with primary applications in brackish water desalination and wastewater purification. 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. Xudong zhang, kuichang zuo, xiaori zhang, changyong. Capacitive deionization system unt digital library. During cdi, ions are adsorbed onto the surface of porous electrodes by applying a. Keywords capacitive deionization desalination electrosorption nanoporous carbon aerogel introduction in recent years, one of the most critical problems affecting people.
Download pdf info publication number us20110147212a1. Simplified prediction of ion removal in capacitive. Anions, ions with a negative charge, are removed from the water and are stored in the positively polarized electrode. Carbonbased electric double layer capacitors for water. Wed like to understand how you use our websites in order to improve them. Jun 11, 2015 recently, capacitive deionization cdi is considered as one of the most promising techniques that meet all of the above requirements 4,5,6,7, because it can be conducted at ambient conditions and. Exceptional capacitive deionization rate and capacity by.
Cn105190808a syrup purification by capacitive deionization. Selfassembled mesoporous carbon mc materials have been synthesized and tested for application in capacitive deionization cdi of saline water. A onedimensional model for water desalination by flow. The system will be built by coupling an emerging desalination technology called capacitive deionization cdi and a solar panel as the power source. Pdf capacitive deionization cdi is an emerging technology for the. The capacitive deionization results demonstrate that the asprepared nitrogendoped porous carbons have a high electrosorption capacity of. Capacitive deionization cdi is energetically favorable for desalinating lowsalinity water.
Capacitive deionization cdi has gained a lot of attention as a promising water desalination technology. Capacitive deionization cdi, a promising desalination technology using pairs of carbon. A capacitive deionization cell comprising a first electrode, an anion membrane adjacent said first electrode forming an anion membraneelectrode conjugate, a cation membrane in spacial relation with said anion membrane defining a fluid flow path between said anion membrane and said cation membrane, and a second electrode adjacent said cation membrane forming a cation membraneelectrode. Carbon electrodes for capacitive deionization request pdf. Facile synthesis of novel graphene sponge for high. Providing safe portable water to small communities with limited access to large infrastructures of power and water supply is a big challenge of great importance, especially in many developing. Figures of merit and control methods for capacitive deionization cdi ali hemmatifar and juan g. Integrating a supercapacitor with capacitive deionization for direct. Pdf water desalination via capacitive deionization. Resistance identi cation and rational process design in. As a promising desalination technology, capacitive deionization cdi have shown practicality and costeffectiveness in brackish water. During cdi, ions are adsorbed onto the surface of porous electrodes by applying a low voltage 1. However at the time when this research was started in 1998, the technology was only at.
Author links open overlay panel jongmoon choi a pema dorji b ho kyong shon b seungkwan hong a. However, a rational designed structure of the electrode materials is. It explains the principle, fields of application and limitations of each technology. 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. It provides a separation process that does not utilize chemical regeneration processes, and thus significantly reduces or completely eliminates secondary wastes associated with.
M l original assignee priority date the priority date is an assumption and is not a legal conclusion. Incorporation of ratelimited transfer between the micro and. Capacitive deionization by amy heldenbrand the objective of this research was to develop a mechanistic and predictive model for capacitive deionization cdi. Versatile applications of capacitive deionization cdibased. By applying a voltage over the electrodes of a cdi cell i. Removal of lead ions from water by capacitive deionization electrode materials derived from chicken feathers t. A process for the capacitive deionization of water with a stack of carbon aerogel electrodes has been developed by lawrence livermore national laboratory. Nitrogendoped porous carbons with high surface area for. The bottlenecks of current carbonbased cdi materials are their limited desalination capacities and timeconsuming cycles, caused by insufficient ionaccessible surfaces and retarded electronion transport.
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 reverse osmosis and electrodialysis. Improved performance and longterm stability of activated. Download fulltext pdf optimal conditions for efficient flowelectrode capacitive deionization article pdf available in separation and purification technology january 2020 with 64 reads. This chapter summarizes the basics and the theory behind capacitive deionization cdi. This file is licensed under the creative commons attributionshare alike 3.
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