Abstract: Embodiments relate to methods for generating selected materials from a natural brine, where the natural brine is sea water, saline water, fresh water, synthetic solutions, or industrial liquid wastes. A natural brine comprising at least a portion of a selected material is heated. CO2 is added and mixes with the natural brine forming a mixture such that the CO2/P is a first predetermined value. The mixture is held so that impurities in the natural brine precipitate as solids leaving a second brine substantially comprising the selected material. The second brine is heated. CO2 gas is injected into the second brine, mixing so that the CO2/P is a second predetermined value. The mixture is held so that the selected material precipitates out and are removed.

Abstract: The present invention relates to a method of cleaning electrolytic cells that includes: (a) directing a base solution comprising water into an array of electrolytic cells; and (b) removing contaminants from at least one of the electrolytic cells with air turbulence provided by an injection of compressed air into the electrolytic cell. The injection of compressed air is provided by an air sparging system in fluid communication with an inlet portion of the at least one electrolytic cell. A self-cleaning electrolytic cell system is further included.

Abstract: A method of the type where a brine solution is converted to an alkali metal hydroxide solution within a diaphragm cell, and the resulting cell liquor from the diaphragm cell is introduced to one or more fuel cells for the conversion of the alkali metal hydroxide to form electricity, the improvement comprising regulating the conversion of alkali metal hydroxide within the fuel cell to a conversion of less than 90%, and then subsequently concentrating the alkali metal hydroxide concentration from the anolyte stream of the fuel cell.

Abstract: A method for concentrating an aqueous caustic alkali produced by a membrane cell process by using a single or multiple effect evaporator system in which the vapor flows in a counter direction to the aqueous caustic alkali flow and the heat recovered from the catholyte circulation line is used as part of the concentration process. In one embodiment, a catholyte heat recovery heat exchanger and flash evaporation chamber are located after the last effect of a multiple effect evaporator system. In another embodiment, the catholyte heat recovery heat exchanger and flash evaporation chamber are located prior to the single or multiple effect evaporator system. In yet another embodiment, the catholyte heat recovery process is used in conjunction with additional heat exchanger processes to further concentrate the final product as desired.

Abstract: An automatic washing apparatus (1) includes: an electrolyzed water generation unit (8) that electrolyzes raw water to which an electrolyte is added to thereby generate electrolyzed water; a bubble generation unit (9) that allows fine bubbles to be contained in the electrolyzed water with use of a generated gas generated in the electrolyzed water generation unit (8) to thereby generate bubble electrolyzed water; a washing unit (4) that discharges the bubble electrolyzed water to a washing object to wash the washing object; and a control unit (2) that controls a discharge timing and discharge amount of the bubble electrolyzed water.

Abstract: The invention provides a process for producing chlorine, alkaline metal hydroxide, and hydrogen which comprises the following steps: (a) preparing a brine by dissolving an alkaline metal chloride source in water; (b) removing alkaline precipitates from the brine prepared in step (a) in the presence of hydrogen peroxide by means of a filter of active carbon, and recovering the resulting brine; (c) subjecting at least part of the resulting brine as obtained in step (b) to an ion-exchange step; (d) subjecting at least part of the brine as obtained in step (c) to a membrane electrolysis step; (e) recovering at least part of the chlorine, alkaline metal hydroxide, hydrogen, and brine as obtained in step (d); (f) subjecting at least part of the brine as recovered in step (e) to a dechlorination step; and (g) recycling at least part of the dechlorinated brine obtained in step (f) to step (a).

Abstract: A process for reducing the concentration of perchlorate in an aqueous concentrated multi-component salt solution comprising treating the salt solution with an amphoteric ion-exchange resin to provide an adsorbed perchlorate and multi anion-containing resin and a perchlorate depleted solution; and removing the perchlorate depleted solution. The multi-anion are selected from chloride, chlorate, perchlorate, sulphate, and dichromate, present in electrolytic processes for the production of sodium chlorate.

Abstract: A process for removing silicon compounds from aqueous NaCl brine includes, first, adjusting a weak brine to a pH value of less than 3 with hydrochloric acid. Iron(III) chloride or other trivalent iron ions are added to the acidified weak brine, the obtained weak brine is then continuously fed to a stirred dissolution vessel which contains undissolved salt in addition to brine. Fresh salt is charged batch-wise and intermittently to the dissolution vessel to produce strong brine. The obtained strong brine is fed to a stirred buffer vessel, the pH value in this buffer vessel being maintained at a level ranging from 5 to 8. A strong-brine flow is continuously withdrawn from the buffer vessel and filtered, and the filtrate containing the added iron and silicon is discharged. Also a system for carrying out this process is disclosed.

Abstract: Processes and apparatus for purifying brine are provided including (1) providing an aqueous brine solution comprising one or more inorganic salts and one or more organic compounds and (2) conducting at least one unit operation for removing organic compounds from the brine solution to obtain a purified brine solution.

Abstract: Electrolysis process in which the anode compartment of an electrolytic cell is fed with at least one brine which has been subjected to a stripping treatment in the presence of at least one stripping agent at a pH less than or equal to the pH of the anode compartment of the electrolytic cell, such brine comprising at least one organic compound before the treatment.

Abstract: Process and apparatus for reducing organic content of brine comprising subjecting a brine solution to at least two purification treatments selected from electrochemical treatment, chlorinolysis, or other chemical oxidation treatment, carbon adsorption, extraction, biological treatment and chrystallizing treatment; wherein the organic content of purified brine is sufficiently low to enable sense of the purified brine in an industrial process.

Abstract: A continuous process for purification of brine contaminated with alkaline earth metals. The process comprises combining the brine with an aqueous solution containing at least one of an alkali metal hydroxide and an alkali metal carbonate with efficient mixing by a micro-mixing device.

Abstract: An integrated process separates salts from salty waters and electrolyzes the salts to produce chlorine products such as chlorine, hypochlorites, chlorates and/or caustic soda.

Abstract: Filter wash methods and apparatuses for chloralkali processes are provided. The filter wash uses in-process fluids from the chloralkali process to wash filters. The in-process fluids may be drawn from a point in the chloralkali process where the in-process fluids contain active chlorine values such as bleach. A filter may then be isolated from the chloralkali process and contacted with the in-process fluids containing active chlorine values to wash the filter. The in-process fluids containing active chlorine values may be operable to oxidize organic material clinging to the filter, thereby cleaning the filter. After washing, the in-process fluids containing active chlorine values may be returned to the chloralkali process to a point at or near where they were drawn from. The filters may be membrane filters. The filters may comprise expanded polytetrafluoroethylene.

Abstract: Disclosed is a process for manufacturing bleach (or sodium hypochlorite) and caustic potash (or KOH) without the need for shipping or storing chlorine gas. Specifically, the present invention relates to the manufacture of potassium hydroxide and chlorine gas, through several process options, for the manufacture of sodium hypochlorite (or bleach), hydrochloric acid (HCl) and/or other chlorinated compounds. The disclosed process allows operating flexibility based on chlorine demand, reduces capital costs and eliminates the need for the transportation and storage of chlorine gas.

Abstract: The present invention relates to a process for producing high purity lithium hydroxide monohydrate, comprising following steps: concentrating a lithium containing brine; purifying the brine to remove or to reduce the concentrations of ions other than lithium; adjusting the pH of the brine to about 10.5 to 11 to further remove cations other than lithium, if necessary; neutralizing the brine with acid; purifying the brine to reduce the total concentration of calcium and magnesium to less than 150 ppb via ion exchange; electrolyzing the brine to generate a lithium hydroxide solution containing less than 150 ppb total calcium and magnesium, with chlorine and hydrogen gas as byproducts; producing hydrochloric acid via combustion of the chlorine gas with excess hydrogen and subsequent scrubbing of the resultant gas stream with purified water, if elected to do so; and concentrating and crystallizing the lithium hydroxide solution to produce lithium hydroxide monohydrate crystals.

Abstract: A continuous method for the treatment of a spent aqueous caustic stream used to scrub a hydrocarbon process stream to remove oxidizable sulfur-containing compounds includes: a. mixing an oxidizing hypochlorous acid stream produced from an aqueous brine solution with the aqueous caustic stream to form a reactive mixed feedstream; b. contacting the reactive mixed feedstream with at least one catalyst to promote the oxidation of the sulfur-containing compounds and the neutralization of the sodium hydroxide; and c. recovering a neutral treated product stream comprising aqueous sodium sulfate, sodium carbonate and sodium chloride that is odorless, non-toxic and environmentally acceptable for discharge into the sea or into a conventional sewage treatment system.

Abstract: A method for the electrolysis of aqueous solutions of hydrogen chloride in order to produce chlorine, characterized in that the following process parameters are maintained for initial operation: the anode half-element is filled with a 5 to 20% strength by weight hydrochloric acid, the concentration of the hydrochloric acid is more than 5% by weight during initial operation, the volumetric flow of the hydrochloric acid through the anode half-element is set in such a way that, at the start of electrolysis, the velocity of the hydrochloric acid in the anode space is from 0.05 cm/s to 0.15 cm/s, the electrolysis is started with a current density of 0.5 to 2 kA/m2, and the current density is then increased continuously or discontinuously until the desired current density is reached.

Abstract: A method of generating basic hydrogen peroxide (BHP) fuel for a chemical oxygen-iodine laser (COIL) using stored alkali chloride, typically potassium chloride, and water. The alkali chloride and water are mixed to form a saturated or nearly saturated aqueous salt solution for use as an anolyte feed to a chlor-alkali cell. The chlor-alkali cell generates alkali hydroxide, hydrogen, and chlorine. Water and oxygen are reacted to form peroxide which is combined with the alkali hydroxide from the chlor-alkali cell to form a dilute solution of BHP, a mixture of hydrogen peroxide and alkali hydroxide, which dissociates into O2H? and ?OH. The BHP is concentrated and the molar ratio of hydrogen peroxide to alkali hydroxide is adjusted to 1:1 before the BHP is supplied to a COIL apparatus as fuel for the lasing process.

Abstract: A method and apparatus for removing BHP contaminants (alkali hydroxide and H2O2) from a recycled aqueous alkali chloride solution stream before the stream is fed to a chloralkali cell so that the contaminants do not impair the operation of a chloralkali cell. Unwanted alkali hydroxide within the recycled alkali chloride brine solution is reacted with chlorine gas and converted into an alkali chloride, which is useful in the operation of the chloralkali cell, and oxygen gas, which is outgassed from the system. Any H2O2 remaining in the recycled stream after elimination of the alkali hydroxide is reacted with chlorine to form HCl and oxygen gas. The HCl raises the pH of the brine solution, after which the pH may be adjusted by the addition of supplemental alkali hydroxide.

Abstract: A method for the reduction of soluble aluminum species in an evaporated salt alkali metal halide brine containing up to 500 ppb aluminum species to provide a brine feedstock suitable for use in a chlor-alkali membrane cell process, said method comprising treating said brine with a magnesium salt in an amount to provide a Mg to Al molar ratio selected from 5-20 to 1 at a Mg concentration selected from 0.5-10 ppm, and sufficient alkali metal hydroxide to provide an excess alkalinity concentration of between 0.1-0.5 g/L alkali metal hydroxide to effect precipitation of a magnesium aluminum hydroxide complex; and removing said complex to provide said brine feedstock.

Abstract: The present invention relates to a method of increasing the concentration of dilute brine in NaCl electrolysis plants using the membrane process, wherein the NaCl required is stored in a mass flow silo with supernatant liquid and is fed continuously from there to the quick dissolver.

Abstract: A chlorination system in which brine is converted to sodium hypochlorite by an electrolyser. Brine (1) fed to the electrolyser (3) is passed through a filter (2) which is capable of adsorbing bromine or hypobromous acid. Some of the sodium hypochlorite produced in an electrolyser (3) is fed back to a point in the brine feed upstream of the filter (2) such that any bromide in the brine is oxidized to bromine or hypobromous acid and therefore adsorbed by the filter (2).

Abstract: This invention relates to methods, systems and installations for concentrating depleted brine produced by the electrolytic decomposition of concentrated brine in chlor-alkali membrane cells and to the efficient use of power, steam and brine. More particularly, this invention relates to the use of depleted brine directly into evaporation systems, which are used to concentrate the brine for reuse in membrane cells or other processes. This invention employs the phenomena that a week unsaturated brine boiling under reduced pressure has a lower boiling point rise (BPR) than a saturated brine boiling at the same or higher pressure. The concentration of depleted brine at a lower boiling point rise improves the operating efficiency of either mechanical vapor recompression and/or steam jet thermocompression. Further, this invention allows for concentrating the depleted brine at temperatures low enough to utilize plastic materials of construction.

Abstract: In a method of removing impurities, especially iodine and/or silica ions, from a salt solution to be used for electrolysis, the salt solution and zirconium hydroxide are brought into contact with each other under acidic conditions, and the zirconium hydroxide adsorbs the impurities. Thereafter, the zirconium hydroxide containing the adsorbed impurities is brought into contact with an aqueous solution at a higher pH value to desorb the impurities from the zirconium hydroxide, thereby enabling the zirconium hydroxide to be recycled.

Abstract: The invention relates to a process for the electrolysis of sodium chloride-containing brine with parallel operation of amalgam electrolysis units (5) and membrane electrolysis units (4) with a common brine circuit using a mercury-resistant oxygen consumable cathode in the membrane electrolysis unit (4).

Abstract: A process for separating chlorine gas from a mixture with other gases is disclosed. In the process, chlorine gas, either as an impure gas or as dissolved gas in hydrochloric acid, is reduced at the cathode of an electrochemical cell to form chloride ions, which are discharged at the anode of the same cell as pure chlorine gas. An apparatus for performing the process is also disclosed.

Abstract: A method to prevent cladding or plating of metals, such as nickel or iron in a continuous production of alkali metal hydroxides which involves several steps: electrolyzing an aqueous alkali metal salt solution forming hydrogen, chlorine and an at least 10% caustic solution at a temperature of from about 75 to about 100 F; and treating said at least 10% caustic solution to create a more concentrated caustic solution while continuously and magnetically removing up to 33% of the metals present in the solution from the at least 10% caustic solution using a first magnet prior to evaporation, flashing and cooling of the at least 10% caustic solution, and then magnetically removing an additional amount of metals from the resultant more concentrated caustic solution again with a second magnet prior to filtration of the more concentrated caustic solution.

Abstract: In removal of sulfate groups and chlorate groups from brine used for electrolysis, concentrated brine used in an electrolysis process or dilute brine whose concentration is decreased by electrolysis is fed to an anode chamber divided by a cation exchange membrane in a brine treating electrolyzer, where the concentrated or dilute brine is electrolyzed to recover chloride ions therein. The concentrated brine is electrolyzed at a rate of decomposition of salt higher than that in the ion exchange membrane electrolysis process of brine. Thereafter, the concentrated or dilute brine is discharged out of the electrolysis process.

Abstract: The present invention relates to a method to control of the presence of nickel and/or iron in a caustic solution using at least two magnets to remove about one third of the nickel and/or iron present in a caustic solution. The method involves passing cell liquor through a first magnet at a flow rate of about 600-900 gallons per minutes removing a significant amount of nickel and/or iron from the cell liquor forming first fluid, then evaporating a significant amount of water out of that first fluid and raising the temperature of that first fluid to above 330 F., then cooling the more concentrated caustic solution to a temperature of between about 75 and 100 F.

Abstract: The method reduces the concentration of multivalent metal cations such as calcium, magnesium, iron, nickel, and chromium in brine solution containing a water-soluble metal chelating agent such as sodium gluconate. The method comprises subjecting the brine to primary brine treatment, and then readjusting the brine solution to a pH ranging from about 1.5 to about 5.5, and contacting the brine solution with at least one resin bed comprising a chelating ion exchange resin, typically at a temperature ranging from about 10.degree. C. to about 90.degree. C. and at a flow rate ranging from about 4 to about 32 resin bed volumes per hour; and recovering the brine solution.

Abstract: The method involves the steps of: exposing a cell liquor containing metal to a first magnet, magnetically removing up to about one third of said metal present in the cell liquor, evaporating a significant amount of water out of that fluid, and raising the temperature of that fluid to above 220 Fahrenheit and adding a small amount of sodium borohydride (NaBH.sup.4) to suppress the reaction of the caustic solution with metal in the manufacturing process, evaporating and flashing off more water from the caustic solution, cooling the solution after evaporation and then flowing it through and around a second magnet to magnetically removing an additional amount of metal the solution, filtering the solution and then magnetically removing an additional amount of metal from said solution forming a final caustic solution having 40-55% by weight caustic.

Abstract: Process for the removal of heavy metal, metalloid and fluoride species present in trace mounts from aqueous brine of use in the production of chlorine and sodium hydroxide by electrolysis in membrane cells or in chlorate production; particularly to said removal by adsorption on hydroxyapatite; and more particularly to adsorption on bone charcoal.

Abstract: The present invention relates to an environmental-friendly process for reducing the content of chloride in a liquor inventory of a chemical pulp mill. According to the invention, in a recovery system for pulping chemicals containing sulphur and an alkali metal, precipitator dust formed in a recovery boiler is collected and withdrawn, dissolved in water and electrolyzed for production of chlorine or hydrochloric acid in the anolyte. Since the dust normally contains a large amount of sodium sulphate, sulphuric acid and sodium hydroxide can also be produced in the electrolysis. To reduce the content of impurities, before the electrolysis, the pH of the aqueous solution is adjusted to above about 10 to precipitate inorganic substances which are separated-off together with flocculated or undissolved substances.

Abstract: The conditions for electrowinning Zn, Ni, Co and Cd metals from baths based on chlorinated ammino complexes of Me(NH.sub.3).sub.n Cl.sub.m type are substantially improved by the addition of small levels of dissolved Br, which considerably reduce the cell voltage without exerting any negative effects on cathodic current yields.