327 results about "Capacitive deionization" patented technology

The polarized electrode flow through capacitor comprises at least one each electrode material, with a pore volume that includes meso and micropores, with contained anionic or cationic groups. The polarized electrodes are in opposite polarity facing pairs, separated by a flow path or flow spacer. Both polarities of the particular attached ionic groups used are ionized at the working pH or composition of the particular feed solution supplied to inlet of the flow through capacitor. The contained groups cause the electrodes to be polarized so that they are selective to anions or cations. The polarized electrode flow through capacitor has better performance compared to identical flow through capacitors made from non-derivitized carbon. The capacitor electrode materials so derivitized provide this polarization function directly without need for a separate charge barrier material.

A method of forming a metal-carbon composite, the method comprising subjecting a precursor composition to a curing step followed by a carbonization step, the precursor composition comprising: (i) a phenolic component, (ii) a crosslinkable aldehyde component, (iii) a polymerization catalyst, and (iv) metal-containing particles, wherein said carbonization step comprises heating the precursor composition at a carbonizing temperature of at least 300° C. for sufficient time to convert the precursor composition to said metal-carbon composite. The produced metal-carbon composite, devices incorporating them, and methods of their use (e.g., in capacitive deionization and lithium ion batteries) are also described.

A capacitive deionization (CDI) system for deionizing water is disclosed. The CDI system comprises at least a flow through capacitor (FTC) module, at least a first supercapacitor, at least a second supercapacitor, at least a third supercapacitor and a controller. The FTC module comprises a plurality electrodes for removing ions from water flowing between the electrodes under an electric field applied between the electrodes. The first supercapacitor is connected between the potential source and the FTC module for amplifying energy provided by the potential source. The second supercapacitor is connected to the FTC module for receiving energy from the FTC module for regenerating the electrodes of the FTC module. The third supercapacitor is adapted for exchanging energy with the FTC module for regenerating the electrodes of the FTC module. The controller is adapted for regulating deionization rate of the water and regeneration of the electrodes of the FTC module.

An electrically regeneratable battery of electrochemical cells for capacitive deionization (including electrochemical purification) and regeneration of electrodes is operated at alternate polarities during consecutive cycles. In other words, after each regeneration step operated at a given polarity in a deionization-regeneration cycle, the polarity of the deionization step in the next cycle is maintained. In one embodiment, two end electrodes are arranged one at each end of the battery, adjacent to end plates. An insulator layer is interposed between each end plate and the adjacent end electrode. Each end electrode includes a single sheet of conductive material having a high specific surface area and sorption capacity, preferably a sheet formed of carbon aerogel composite. The batter further includes a plurality of generally identical double-sided intermediate electrodes that are equidistally separated from each other, between the two end electrodes. As the electrolyte enters the battery of ells, t flows through a continuous open serpentine channel defined by the electrodes, substantially parallel to the surfaces of the electrodes. By polarizing the cells, ions are removed from the electrolyte and are held in the electric double layers formed at the carbon aerogel surfaces of the electrodes. As the electrodes of each cell of the battery are saturated with the removed ions, the battery is regenerated electrically at a reversed polarity from that during the deionization step of the cycle, thus significantly minimizing secondary wastes.

The present device is a microchannel separator that uses a separation driving force created by an electric field. An ionic fluid flows through the microchannels and is subjected to an electric field by two spaced apart parallel electrodes possessing an electric charge. The ions in the ionic fluid are attracted towards the charged electrodes and thus are concentrated in the region of flow near the charged electrodes and depleted from the central region of flow between the charged electrodes. The charged electrodes are insulated from the ionic fluid by an impermeable barrier which prevents arcing and adherence of the ions to the charged electrodes. After a sufficient length of passage of the ionic fluid through a main channel two blocking plates separate the flow into a central and two outer output channels. The central channel draws a portion of the ionic fluid from the central region of the main channel that has fewer ions than the ionic fluid in the regions near the charged electrodes. The concentrated ionic fluid in the outer channels is discharged separately from the central channel.

A method for fabricating a porous carbon material possessing a hierarchical porosity, the method comprising subjecting a precursor composition to a curing step followed by a carbonization step, the precursor composition comprising: (i) a templating component comprised of a block copolymer, (ii) a phenolic component, (iii) a dione component in which carbonyl groups are adjacent, and (iv) an acidic component, wherein said carbonization step comprises heating the precursor composition at a carbonizing temperature for sufficient time to convert the precursor composition to a carbon material possessing a hierarchical porosity comprised of mesopores and macropores. Also described are the resulting hierarchical porous carbon material, a capacitive deionization device in which the porous carbon material is incorporated, as well as methods for desalinating water by use of said capacitive deionization device.

The invention discloses an MXene-based flexible composite negative electrode material and a preparation method thereof. According to the MXene-based flexible composite negative electrode material andthe preparation method thereof, a transition metal sulfide is loaded on a two-dimensional layered structure of the MXene material through a hydrothermal method. The agglomeration effect of the MXene material is overcome, and the collapse of a layered structure is prevented. Meanwhile, the energy density of the composite material is improved. The MXene material with high conductivity acts as a three-dimensional conductive network skeleton, so that the conductivity and the mechanical strength of the composite material are enhanced. The volume expansion of the transition metal polysulfide material in the charging process is buffered. Meanwhile, the material has good charge-discharge cycle stability. The composite material and expanded graphite are combined to prepare a self-supporting high-flexibility negative electrode material. In the charging and discharging process, the hydrophilic MXene material has high affinity to polysulfides. The electrochemical performance and the capacitive deionization performance of the composite negative electrode material can be further improved. Sulfides generated by transition metal sulfides are eliminated. The shuttle effect of the polysulfides is limited, and the service life of the negative electrode material is prolonged.

The invention discloses a method for flow-electrode capacitive deionization (FCDI)-based desalination and application. According to the method, a direct current voltage stabilization power supply, a flow electrode, a dual-channel peristaltic pump, an FCDI module unit, a small-size peristaltic pump, a conductivity meter, an organic glass fixing device, a stainless steel interface and an electrode connection splice are involved; one end of each of two pump pipes of the dual-channel peristaltic pump is arranged in each of anode chamber flow electrode liquid and cathode chamber flow electrode liquid, and the other end of the pump pipe is connected with the stainless steel interface in the lower part of the organic glass fixing device; the flow electrode enters the FCDI unit module through the stainless steel interface through pressure provided by the dual-channel peristaltic pump; incoming water is pumped into the FDCI unit module with a prepared sodium chloride solution with different concentration at certain flow speed through the small-size peristaltic pump; the conductivity meter is used for measuring the conductivity concentration of discharged water. A reaction device used in the method is simple in structure, low in operation cost and easy to operate, and no chemicals is fed; automatic control and on-line monitoring are easy to implement; the method is low in energy consumption, and the preparation cost of the electrode is lowered; the method can be applied to the technical field of environmental engineering and water treatment.

Disclosed herein is an electrode for capacitive deionization device including an active material, a waterborne polyurethane, and a conducting agent. Disclosed herein too is a method of manufacturing the electrode and a capacitive deionization device employing the electrode.

A capacitive deionization device includes; at least one flow path configured for influent water flow, at least one pair of electrodes, at least one charge barrier disposed between the at least one flow path and a corresponding electrode of the at least one pair of electrodes, and at least one electrolyte solution disposed between the at least one electrode of the at least one pair of electrodes and a corresponding charge barrier of the at least one charge barrier, wherein the at least one electrolyte solution is different in at least one of ionic concentration and ionic species from the influent water.

A capacitive deionization electrode may include a conductive material and a polymer on a surface of the conductive material. The polymer may have at least one functional group in a single polymer chain.

Capacitive deionization (CDI) is a non-membrane and chemical-free technique for water purification, used-water recycling, and seawater desalination. Ionic contaminants in the waters are retained by a static electric field built within the critical component of CDI, which is known as flow through capacitor (FTC). Apparently, parameters enhancing the field strength of FTC and electrode efficiency are the keys to the performance of CDI. The FTC of the present invention is formed by a plurality of monopolar and a plurality of bipolar electrodes, and a plural number of perforated holes are disposed on the FTC electrodes in a pattern that allows certain water flow rate and residence time to yield the highest efficiency of electrode utilization.

The invention relates to a continuous wastewater treatment device utilizing membrane capacitive deionization. An upper cover plate and a lower cover plate are coaxially installed at the upper end and the lower end of a cylindrical shell, a water inlet nozzle and a water outlet nozzle which are communicated with the interior of the shell are respectively formed in the axis part of the upper cover plate and the axis part of the lower cover plate, a water collecting plate is coaxially installed on the upper cover plate in the shell, conducting rods are uniformly and axially distributed on the periphery of the shell at intervals, a lower distribution board and an upper distribution board are coaxially installed in the shell between the water collecting plate and a water distributing plate and are of a pair of metal boards, and a plurality of groups of processing module components are coaxially installed between the two distribution boards, wherein each group of processing module component comprises an upper current collecting plate, a membrane carbon positive electrode, a diaphragm, a membrane carbon negative electrode and a lower current collecting plate. According to the continuous wastewater treatment device, the membrane electrode is integral and is prepared by a carbon electrode and an ion membrane through spraying a cation exchange coating on a cathode and spraying an anion exchange coating on an anode, the thickness of the ion exchange layer is less than 10mu, and the membrane electrode has small resistance and large capacitance compared with those of a membrane electrode on which an ion membrane is directly added.

The invention discloses a membrane capacitive deionization device for circulation treatment and a treatment method. The membrane capacitive deionization device comprises a membrane capacitance deionization component, a step-up/step-down converter, a direct-current (DC) power supply, a raw water storage tank, a middle liquid storage tank, a regenerated water storage tank, a fresh water storage tank, a conductivity monitor, a water pump, a power valve, a check valve and a DC/DC converter. Based on a technique of double-electrode layer desalting principles, the membrane capacitive deionization device is capable of removing salt and storing energy; and in the regeneration process of a capacitive deionization unit, the stored energy can be released. Collection of the part of energy can be achieved, and the collected energy can be used as an external power supply of the capacitive deionization unit for desalting operation. In order to achieve the purpose of maximization of energy storage, the step-up/step-down converter is introduced, energy recycling can be achieved, and the energy consumption can be reduced. Due to the design of the experiment device disclosed by the invention, an effect of multi-level treatment on strong brine can be achieved.

The invention belongs to the fields of water treatment and resource recycling and discloses a capacitive deionization (CDI) coupling electrocatalysis system and a method for cooperatively removing heavy metal and organic pollutants in water by using the CDI coupling electrocatalysis system. Under the conditions of an external electric field (smaller than 2V), a capacitive electrostatic adsorptioneffect is coupled with an electrocatalytic oxidation degradation effect, and the heavy metal and the organic pollutants are simultaneously moved. The CDI coupling electrocatalysis system disclosed bythe invention has the beneficial effects cooperative removal of the heavy metal and the organic pollutants in the water is realized by using electrodes with catalytic activity, and the defect and theproblem that a traditional water treatment technology only treats a single pollution system is overcome/solved. The reaction system has the advantages of simplifying a treatment technology, shorteningthe flow, reducing secondary pollution and facilitating scale and industrial application.

Systems and methods are described that combine capacitive deionization (CDI) and electro-deionization (EDI) mechanisms for deionizing aqueous or non-aqueous solutions. The inventive systems and methods modify certain known coatings or films by perforating the films with pin holes and using spacers that separate the coatings from the electrodes. Benefits derived from these improvements include: (a) maintaining a high level of purification; (b) increasing by as much as 25% the rate of expulsion of ions during regeneration; (c) increasing by as much as 50% the rate of electrical discharge of the cell; (d) decreasing the regeneration time (producing as much as 33% more purified water per unit of time); (e) reducing by as much as 25% the power required; and (f) improving the recovery of the system to as much as 85%.