1853results about "Electrodialysis" patented technology

The invention discloses a monovalent selective cation exchange membrane, a preparation method thereof and an electrodialysis device, and relates to the technical field of ion exchange membranes. The preparation method of the monovalent selective cation exchange membrane comprises the following steps: soaking a cation exchange membrane loaded with a photoinitiator in a co-deposition modification solution containing dopamine, polyethyleneimine and chitosan, carrying out a co-deposition reaction under radiation initiation of ultraviolet light, taking out the cation exchange membrane after the reaction is finished to obtain a co-deposition modified membrane, and then carrying out heat treatment to obtain the monovalent selective cation exchange membrane. The monovalent selective cation exchange membrane is obtained. The ultraviolet light initiator and chitosan with certain adhesion are introduced in the co-deposition process, so that the co-deposition speed of dopamine and polyethyleneimine on the surface of the film is promoted, meanwhile, a base film and a co-deposition modified layer can be connected, the stability of the modified film is improved, the pore size screening effect is improved, and the service life of the film is prolonged. And moreover, ion exchange sites of the modified membrane are not occupied, monovalent and multivalent cations are effectively separated, and meanwhile, good ion flux is achieved.

Thin film composite cation exchange membranes and systems and methods thereof, and, more particularly, thin film composite cation exchange membranes for monovalent / divalent ion separation in electrodialysis and thin film composite cation exchange membranes for achieving Li separation.

Air flows across an air-liquid interface such that liquid desiccant flowing through the interface absorbs water from the air and is thereby diluted to form an output stream. The output stream is circulated through an electrodialytic stack having a central ionic exchange membrane and first and second outer ionic exchange membranes. A redox shuttle loop circulates around the first and second outer ionic exchange membranes. A voltage is applied across the electrodialytic stack, which regenerates the liquid desiccant.

The invention relates to the technical field of membrane separation and resource recovery, and discloses a bipolar membrane electrodialysis device for synchronously capturing carbon dioxide, extracting lithium and producing lithium carbonate. The device utilizes a selective bipolar membrane electrodialysis system to extract lithium ions from liquid resources such as spodumene leachate, brine, oil and gas field wastewater, seawater and the like, and converts the lithium ions into lithium hydroxide. And meanwhile, introducing flue gas containing carbon dioxide into the generated lithium hydroxide solution by using a gas disperser to generate lithium carbonate. Therefore, mineralization capture of carbon dioxide in the flue gas, extraction of lithium ions in liquid resources such as spodumene leachate, brine, oil and gas field wastewater and seawater and production of lithium carbonate are synchronously realized, waste is treated by waste, and the method has the advantages of simple process, high lithium ion yield, short period, environmental friendliness, no pollution, continuous production and the like, and is suitable for industrial production. The method has important significance on carbon dioxide capture, lithium resource recovery and development of the new energy industry.

Molecular electrocatalytic systems for ammonia production from wastewater nitrate are described. The electrocatalytic systems use ammonia-selective homogeneous molecular NOsRR catalysts in real wastewater.

The present disclosure relates to an electrochemical device for extracting copper from copper-containing wastewater and an extraction method using the same. Cu-based chalcogenide, as an electrode material, forms an electrochemical device with other electrodes. The device is an electrocatalytic coupling deionization system with electrochemical oxidative decomplexing performance, and has a good selective removal effect of Cu2+ from organic complex copper-containing wastewater, strongly acidic wastewater, and wastewater interfered by high concentration salt ions and heavy metal ions. With this device, the organic complex pollutant Cu-EDTAn can be effectively decomplexed to complete the extraction of Cu2+.

The utility model discloses an electrodialysis device with an automatic hydraulic station, and belongs to the field of electrodialysis devices. The hydraulic cylinder is connected with the electrodialysis assembly; an oil tank; one end of the pump body is communicated with the oil tank; the inlet end of the one-way valve is communicated with the other end of the pump body, and the outlet end of the one-way valve is communicated with the hydraulic cylinder; one end of the pressure sensor is communicated with the oil tank, and the other end of the pressure sensor is communicated between the outlet end of the one-way valve and the hydraulic cylinder; one end of the electromagnetic valve is communicated with the oil tank, and the other end of the electromagnetic valve is communicated between the outlet end of the one-way valve and the hydraulic cylinder; and the controller is electrically connected with the pressure sensor and the electromagnetic valve. The utility model has the technical effects that the pressure can be automatically controlled conveniently, and the pressure can be prevented from being too large or too small.

Provided is a two-membrane eluent generator and a chromatography detection apparatus. The two-membrane eluent generator includes a stock solution channel; an eluent channel, a first ion-exchange membrane set being arranged between the eluent channel and the stock solution channel, the first ion-exchange membrane set including at least one ion-exchange membrane; a regenerant solution channel, a second ion-exchange membrane set being arranged between the eluent channel and the regenerant solution channel, the second ion-exchange membrane set including one bipolar membrane, wherein hydrogen ions or hydroxide ions generated at the bipolar membrane from electrolysis of a regenerant solution respectively enter different sides of the bipolar membrane, and impurity ions are prevented from entering the eluent channel through the bipolar membrane. The chromatography detection apparatus provided in present disclosure includes the two-membrane eluent generator. The present disclosure applies a bipolar membrane between the regeneration channel and the eluent channel, and is thus capable of supplying corresponding hydrogen ions or hydroxide ions for the eluent channel while preventing impurity ions in the regenerant solution from entering the eluent channel, thereby increasing the purity of the eluent.

The invention relates to a method and device for preparing formic acid and hydrogen through electrolysis. According to the method, an alkaline electrolyte containing methanol is electrolyzed, a cathode electrode for electrolysis takes foamed nickel as a base material to load iron-cobalt-nickel nanoparticles, an anode electrode takes foamed nickel as a base material to load cobalt-nickel particles, and a cathode chamber generates hydrogen; and collecting the electrolyte obtained after electrolysis in the anode chamber in the electrolysis device for bipolar membrane electrodialysis, and obtaining a primary formic acid solution in the acid chamber of the bipolar membrane electrodialysis device. The device comprises an electrolysis device and a bipolar membrane electrodialysis device, a cathode electrode, a first bipolar membrane, a positive membrane, a negative membrane, a second bipolar membrane and an anode electrode are sequentially arranged in the bipolar membrane electrodialysis device, and an acid chamber, a salt chamber and an alkali chamber are sequentially divided among the first bipolar membrane, the positive membrane, the negative membrane and the second bipolar membrane. Compared with an existing methyl formate hydrolysis method for preparing formic acid, an intermediate methyl formate is toxic to a human body, formic acid and hydrogen can be safely prepared, and production safety accidents are prevented.

The invention relates to the technical field of membrane separation, and discloses a double-side-chain anion exchange membrane as well as a preparation method and application thereof. The anion exchange membrane comprises a plurality of polyphenyl ether molecular chains, the polyphenyl ether molecular chain has a structure as shown in a formula I; # imgabs0 # Q1, Q2, Q3 and Q4 are each independently a group represented by formula II, a group represented by formula III, Br or H; at least two of Q1, Q2, Q3 and Q4 are a group as shown in a formula II and a group as shown in a formula III; at least two polyphenyl ether molecular chains of # imgabs 1 # are connected through a structure Ar from a cross-linking agent; according to the double-side-chain anion exchange membrane, two long-chain hydrophobic alkyl side chains are introduced into a polyphenyl ether molecular chain, so that the content of an active ion exchange matrix in the anion exchange membrane is remarkably increased, and the performance of the anion exchange membrane is improved.

This lithium recovery device 10C is provided with a processing tank 1 that is partitioned into a supply tank 11 and a recovery tank 13 by a lithium ion-conducting electrolyte membrane 2. In order to selectively move Li+ to an aqueous solution RS in the recovery tank 13 from an aqueous solution SW in the supply tank 11, the aqueous solution SW containing Li+ and other metal ions Mn+, this lithium recovery device 10C is also provided with: a first power supply 51 which is connected between a first electrode 31 that has a porous structure and is arranged so as to be in contact with a supply tank 11-side surface of the electrolyte membrane 2 and a second electrode 32A that is arranged within the recovery tank 13, in such a manner that the first electrode 31 functions as the positive electrode; and a sub power supply 53 which is connected in series to the positive electrode of the first power supply 51, while having the positive electrode thereof connected to a sub electrode 41 that is arranged within the supply tank 11 at a distance from the electrolyte membrane 2.

The invention belongs to the technical field of geotechnical engineering sludge solidification, and particularly relates to an integrated test system and method for solidifying and repairing polluted bottom mud through vacuum electroosmosis. According to the method, the change of the water content and the electric conductivity of the polluted bottom mud in the electroosmosis treatment process can be monitored in real time, and the change of the pollution concentration of the polluted bottom mud can be calculated in real time according to the change of the water content and the electric conductivity, so that the problems that a traditional test method needs sampling detection, steps are tedious and a result cannot be obtained in real time are solved; no special equipment is needed for measuring the concentration and the moisture content of the pollutants, so that the cost is saved; pollutants in the polluted bottom mud are discharged into the water collecting assembly along with sewage, so that the decontamination effect is ensured; the polluted bottom mud in the mud inlet assembly is sucked into the vacuum container through the negative pressure assembly, so that the uniformity of the polluted bottom mud is ensured; along with the proceeding of the test, the vacuum container compresses the polluted bottom mud, so that the vacuum electroosmosis dehydration and decontamination process is accelerated.

The present invention pertains to an improved process for production of nutritional products, such as e.g. infant formulas, containing milk protein and milk saccharide. The invention is particularly useful for the production of demineralized nutritional products and provides both the final nutritional product as well as milk saccharide-containing milk protein serum ingredients useful for the production of such nutritional products.

The invention provides an alkali metal group ion selective permeable membrane, a preparation method and a lithium, rubidium and cesium extraction method and system, and the membrane is prepared by taking polyphenylene sulfide, Zr (HPO4) 2 and a high-molecular polymer adhesive as raw materials through mixing, fibration treatment and compression molding processes. Based on the weak dipole adsorption characteristic between the sulfur position of high-crystallization polyphenylene sulfide and alkali metal cations, efficient screening of monovalent alkali metal ions (Li < + >, Rb < + > and Cs < + >) and multivalent impurity ions (Mg < 2 + >, Al < 3 + > and Fe < 2 + >) is achieved, and the method can be used for extracting rubidium and cesium. The ion selective permeable membrane has excellent mechanical properties, high separation efficiency and corrosion resistance, and is low in production cost; and finally, the multiple targets of lepidolite leaching liquid impurity removal and lithium rubidium cesium synergistic extraction are achieved.

The application discloses a bipolar membrane electrodialysis device, which comprises an outer box body and further comprises a liquid inlet mechanism, a plurality of electrodialysis mechanisms and a plurality of filtering mechanisms. The filtering mechanism comprises a filtering box, a driving filtering assembly and a liquid feeding assembly. The driving filtering assembly comprises a motor installed on the top of the filtering box, the output shaft of the motor is fixedly connected with a threaded rod, the outer periphery of the threaded rod is threadedly connected with a filtering plate slidingly connected to the inner wall of the filtering box, and the bottom inner wall of the filtering box is fixedly connected with a plurality of plug rods matched with filtering holes of the filtering plate. Raw water is delivered to the inside of the filtering box through the liquid inlet mechanism, is actively filtered without turbulence through the driving filtering assembly, is delivered to the corresponding electrodialysis mechanism through the liquid feeding assembly and is further subjected to electrodialysis treatment. The filtering plate and other components are arranged to filter out the solid impurities mixed in industrial glucose acid salt, so that the bipolar membrane electrodialysis process and the bipolar membrane body are not affected.

A sequentially stacked multi-stage desalination system includes a single pair of electrodes, including an anode and a cathode; at least one ion concentration polarization device; and at least one electrodialysis device coupled with the ion concentration polarization device and configured to receive liquid flow from the ion concentration polarization device. Each ion concentration device and electrodialysis device is positioned between the anode and the cathode.

Plant for electrically producing sodium carbonate or bicarbonate Plant for electrically producing sodium carbonate (Na2CO3) comprising: (A) an electrodialyzer cellstack to electrodialyze a sodium chloride (NaCl) aqueous solution into a sodium hydroxide (NaOH) solution and into a hydrochloric acid (HCl) solution, wherein the electrodialyzer cellstack is operated in at least 2 production rates on a given time period; (B) carbonating mean(s) to partially or totally carbonate the NaOH solution with CO2 into a Na2CO3 solution; (C) storage mean(s) of the NaOH solution or of the Na2CO3 solution; (D) a crystallizer equipment to concentrate Na2CO3 solution and to produce Na2CO3 crystals and a mother liquor; and wherein the storage means of the NaOH solution, or of the Na2CO3 solution, is of a volume sufficient to operate the crystallizer equipment in a constant production rate in the said time period.

The invention relates to a method for simultaneously preparing lithium hydroxide and sulfuric acid. The invention provides a method for simultaneously preparing lithium hydroxide and sulfuric acid, which comprises the following steps: preparing a bipolar membrane electrodialysis device which comprises a first bipolar membrane, an anion exchange membrane, a cation exchange membrane and a second bipolar membrane, and forming an acid chamber between the first bipolar membrane and the anion exchange membrane, a salt chamber is formed between the anion exchange membrane and the cation exchange membrane, and an alkali chamber is formed between the cation exchange membrane and the second bipolar membrane; a lithium sulfate aqueous solution is added into a salt chamber of the bipolar membrane electrodialysis device, a sulfuric acid aqueous solution is added into an acid chamber, and a lithium hydroxide aqueous solution is added into an alkali chamber; and discharging the desalted solution formed in the salt chamber of the bipolar membrane electrodialysis device, discharging the sulfuric acid aqueous solution formed in the acid chamber, and discharging the lithium hydroxide aqueous solution formed in the alkali chamber.

The invention belongs to the technical field of sewage treatment equipment, and particularly relates to a method and a device for preparing a sewage treatment agent by using red mud as a raw material, the device comprises an electrodialysis shell, a membrane stack and an electrode plate, and further comprises a non-stop reversing mechanism. An inner cavity of an electrodialysis shell is divided into a plurality of operation grooves, an electrode corresponding to at least one operation groove is reversed, and meanwhile, under the action of a driving part, the plurality of operation grooves and two groups of electrodes generate relative motion, so that the parts, separated in the plurality of operation grooves, of a membrane stack are opposite to the reversed electrodes in sequence, and the membrane stack is separated from the electrodes. And the operation groove corresponding to the reverse electrode only occupies one part of the inner cavity of the electrodialysis shell, so that the rest part of the inner cavity of the electrodialysis shell is still normally subjected to electrodialysis operation, and the non-stop reverse descaling operation is further realized.

The invention provides a method for accurately regulating and controlling the water quality of cold water in a rotor of a phase modifier, which comprises the following steps: accurately regulating and controlling the water quality of the cold water in the rotor through a bipolar membrane reactor, a rectifier and a control system; the anion receiving liquid circularly circulates between the anion receiving chamber and the anion receiving box, the rotor internal cooling water circularly circulates between the rotor internal cooling water chamber and the raw water tank, and the phase modifier rotor internal cooling water can be introduced into the raw water tank through a bypass and returns to the rotor internal cooling water system from the raw water tank; the water quality of rotor internal cooling water introduced into the raw water tank is monitored in real time through an online pH meter and an online conductivity meter of an internal cooling water circulation pipeline, and parameters of applying direct current to an operation membrane stack are regulated and controlled through a rectifier. According to the invention, the controllability is stronger, the stability is better, the water quality of the cold water in the rotor can be accurately regulated and controlled and recycled, an ion exchanger is not required to be arranged for ion exchange desalination, the energy consumption is low, and the pollution is avoided.

The invention relates to a method for removing thermally stable salt by electrodialysis, which comprises the following steps: i) providing an electrochemical reaction membrane stack which comprises a cathode plate, an anode plate and at least one repeatable unit arranged between the two polar plates, an electric field exists between the cathode plate and the anode plate, each repeatable unit comprises a pure water channel, a desalination channel and an alkali liquor channel in the direction from the cathode plate to the anode plate, the pure water channel is limited by an anion exchange membrane and a cation exchange membrane, the desalination channel is limited by the cation exchange membrane and the anion exchange membrane, and the alkali liquor channel is limited by the anion exchange membrane and the anion exchange membrane; ii) introducing pure water into the pure water channel, introducing raw water into the desalination channel, introducing alkali liquor into the alkali liquor channel, and iii) withdrawing a product stream from the desalination channel; wherein the raw water contains an organic amine compound and a heat-stable salt. The method provided by the invention realizes removal of thermally stable salts by using an electrochemical reaction membrane stack.

The invention relates to the electrochemical production of hydrogen and lithium hydroxide from Li+-containing water using a LiSICon membrane. The objective is to provide a process that can be operated economically on an industrial scale. In particular, the process should exhibit high energy efficiency and achieve a long membrane service life even when the feed contains impurities that are detrimental to LiSICon materials. A special aspect of the process is that the lithium is selectively separated by the membrane and water is electrolyzed simultaneously within the cell. A key aspect of the process is that the electrochemical process is carried out in an alkaline environment, specifically at pH 9 to 13. The pH value is adjusted by adding an alkaline compound to the feed.

The present invention relates to a system for capturing carbon dioxide from an air stream. The system includes a carbon dioxide capturing unit that includes a humidity / temperature adjusting unit with an evaporative cooling unit and a CO2 adsorbing unit. The CO2 adsorbing unit includes a sorbent column made of polyamine-Cu (II) complex resin. The humidity / temperature adjusting unit receives air stream from ambient atmosphere and process the air stream to obtain a humidity-adjusted air stream. The CO2 adsorbing unit receives the humidity-adjusted air stream to pass through the sorbent column. The sorbent column selectively adsorbs the CO2 from the humidity-adjusted air stream. The sorbent column is regenerated using an alkaline stream to separate the adsorbed CO2 from the sorbent column.

The invention relates to an electrodialysis device for the desalination of water for oil and gas applications comprising: a membrane stack comprising alternating cation- and anion-exchange membranes (2.1, 2.3) and a plurality of spacers (2.2, 2.4), each spacer being arranged between two successive membranes; wherein at least one of the spacers (2.2, 2.4) comprises a recessed area (3.2) and a non-recessed area (3.3), a central opening (3.1) within the recessed area (3.2); the spacer (2.2, 2.4) is provided with at least four orifices (3.4, 3.5) within the non-recessed area (3.3); and with respective channels (3.6) which connect at least two of the orifices (3.4) with the central opening (3.1); and one membrane (2.1, 2.3) is accommodated in the recessed area (3.2).The invention also relates to a water desalination process using the electrodialysis device mentioned above.

The invention relates to a method for extracting lithium from a salt lake and synchronously removing silicon and boron. The method comprises the following steps: pre-treating and filtering lithium-containing brine; carrying out reverse osmosis concentration treatment to concentrate lithium to be more than 2.5 g / L; carrying out nanofiltration treatment to remove magnesium, calcium and sulfate ions; treating by adopting an electrodialysis system to obtain a high-silicon and high-boron desalted solution and a low-silicon and low-boron lithium concentrated solution; the low-silicon and low-boron lithium concentrated solution is treated with chelating resin and boron removal resin, so that magnesium and calcium ions are smaller than or equal to 2 mg / L, boron is smaller than or equal to 20 mg / L, and the refined lithium concentrated solution is obtained; concentrating by an evaporation system, adding a precipitant, precipitating, filtering, washing, crushing and demagnetizing to obtain a low-silicon low-boron battery-grade lithium carbonate product. The invention further discloses a system for extracting lithium from the salt lake and synchronously removing silicon and boron, the complex and low-efficiency boron removal and silicon removal nanofiltration process is adopted, and concentration of lithium and efficient removal of silicon and boron are synchronously achieved; silicon scaling pollution caused by membrane separation and heat exchanger tube nests is avoided, and deep removal of silicon and boron is realized.

The utility model relates to amine liquid purification, and provides a system for purifying amine liquid, which comprises an amine liquid supply system, a demineralized water supply system, an electrode water supply system, an electrodialyzer and a cleaning system, the amine liquid supply system, the demineralized water supply system, the electrode water supply system and the cleaning system are connected with the inlet end and the outlet end of the electrodialyzer at the same time. The system for purifying the amine liquid can efficiently purify the amine liquid, and after the amine liquid is purified, the index is higher, the loss is lower, and the cost is lower.

The invention discloses a method for converting lithium hydroxide into lithium carbonate. The method comprises the following steps: S1, preparing or taking a lithium hydroxide solution and a carbonate solution; s2, putting the lithium hydroxide solution and the carbonate solution into electrodialysis equipment, and carrying out electrodialysis treatment; and S3, after electrodialysis is finished, collecting a lithium carbonate solution, and sequentially carrying out lithium precipitation and solid-liquid separation on the lithium carbonate solution to obtain the battery-grade lithium carbonate. According to the method for converting lithium hydroxide into lithium carbonate disclosed by the invention, CO2 is replaced by carbonate, so that the generation of lithium bicarbonate is avoided, the lithium carbonate and the byproduct alkali liquor are directly obtained, the raw material source is wide, the preparation condition is mild, the production cost is greatly reduced, and the method has huge potential economic benefits.

The present invention relates to a monovalent selective cation exchange membrane and a preparation method thereof, belonging to the technical field of cation exchange membranes. The specific steps are: weighing DA and ammonium persulfate and adding them to a buffer solution to obtain a PDA coating solution, pouring the PDA coating solution on the surface of a base membrane for soaking, depositing a PDA coating on the surface of the activated base membrane to obtain membrane I; dissolving zirconium tetrachloride and 2-aminoterephthalic acid in DMF, then solvent-thermally synthesizing an amino-functionalized MOF (UIO-66-NH2) under acidic conditions, weighing PEI and MOF (UIO-66-NH2) powders and adding them to a buffer solution, then pouring them on the surface of membrane I, depositing a PEI-MOF composite coating to obtain membrane II, and air-drying membrane II to obtain a monovalent selective cation exchange membrane. It can be seen that the present invention can prepare a low-cost, highly selective, and stable-performance monovalent selective cation exchange membrane by modifying the cation exchange membrane through a simple and easy-to-operate method.

The invention belongs to the technical field of impurity separation, and particularly discloses a method for separating and purifying impurities in a process for preparing glyoxylic acid through oxalic acid electrolysis, a crystallization kettle is included, an isolation device is arranged in the crystallization kettle, and the isolation device comprises a conical top cover, a conveying pipe, an annular filter screen, a directional conveying assembly and a sealing assembly; the conical top cover is arranged at the axis of the crystallization kettle, an opening of the conical top cover faces downwards, and a plurality of fixing rods are fixedly connected between the top of the conical top cover and the inner wall of the side face of the crystallization kettle. According to the method, glyoxylic acid product solutions with different concentration specifications and the high-purity glyoxylic acid crystal can be obtained after the electrolyte is sequentially subjected to pre-evaporation, electrodialysis, secondary evaporation, cooling crystallization, solid-liquid separation, washing and drying and other procedures, so that the prepared high-purity glyoxylic acid crystal can be popularized and applied in the field of high-end medicine.

A bipolar membrane in which a cation-exchange membrane and an anion-exchange membrane are joined to each other, wherein a leakage ratio of gluconic acid at 60° C. is not more than 1.0%, and the cation-exchange membrane is supported by a polyolefin reinforcing member and, further, contains a polyvinyl chloride.