Abstract: A method for extracting and recycling chromium from hexavalent chromium-containing residues includes the following steps: 1) adding water to the hexavalent chromium-containing residues and mixing uniformly; 2) adding sodium sulfate, sodium chlorate and sulfuric acid to a solution obtained in step 1) and stirring sufficiently to obtain a mixed liquid; 3) treating the mixed liquid by a hydrothermal method or direct heating; 4) after the heating treatment, naturally cooling a solid-liquid mixture to room temperature for holding; 5) separating solid residues and a chromium-containing supernatant, and washing filtered residues with water and then drying; 6) precipitating the supernatant and the water used for washing the filtered residues with a precipitant CaCl2, then centrifugally washing, dewatering and drying the precipitates; and 7) recycling a chromium-containing solution for returning to a work section, or for a treatment of recycling chromium.

Abstract: A process for preparing sodium bicarbonate particles, comprising the steps of: (a) adding at least one alkali metal carbonate to an aqueous solution in order to form an aqueous composition; wherein the alkali metal carbonate comprises sodium carbonate and wherein the aqueous composition comprises at least one polycarboxylic acid and/or the salts thereof, in an amount of at least 200 ppm based on the weight of the aqueous composition; and (b) precipitating solid particles comprising sodium bicarbonate crystals and separating said sodium bicarbonate particles from the aqueous composition, in order to obtain sodium bicarbonate particles and an aqueous mother liquor.

Abstract: A method including electrolysis processing using sulfate-based electrolytes includes precipitating sodium sulfate decahydrate from a salt solution and then redissolving sodium sulfate decahydrate to prepare feed of electrolyte solution for the electrolysis processing. Front-end processing may be used to treat mixed salt solutions, including brine solutions. Calcium sulfate reagent may provide a sulfate source to regenerate electrolyte solution following carbon capture, and with carbon dioxide being sequestered in the form of calcium carbonate.

Abstract: A process for the joint production of crystalline sodium bicarbonate and another alkali compound, in which the step for producing such alkali compound generates CO2 as a byproduct, at least a portion of which is used as a feed to the sodium bicarbonate production step. The produced alkali compound is preferably crystalline sodium sulfite. The joint production process preferably employs as feedstock one or more sodium carbonate liquors derived from trona ore. A gas feed which contains CO2 byproduct is subjected to a gas treatment which may include water removal and/or compression before it is used to produce sodium bicarbonate crystals from a sodium carbonate liquor. Such gas feed may comprise a reactor offgas exiting a sulfite reactor; a vent gas exiting a feed or surge tank; a decarbonation gas exiting a decarbonation unit; a vent gas vented from a crystallizer heater; or combinations of two or more thereof.

Abstract: Disclosed is a boron recovering device including: an aeration-type water-channel reactor including a water channel; at least one aeration unit disposed in the water channel and aerating a boron-containing solution by passing it through the water channel to deposit boron in the form of borax; and a precipitation bath precipitating the deposited borax in the boron-containing solution having passed through the aeration-type water-channel reactor and separating a filtrate by overflowing, a boron recovering device, a method of recovering boron, and a boron recovering system.

Abstract: A potash-extraction system and method for extracting potash from a brine containing potash without the use of water-consuming evaporation ponds or additional chemicals is disclosed. The potash processing system uses a mechanical-vapor recompression (“MVR”) cycle to separate salt and then potash from a sylvinite brine containing salt and potash. In embodiments, the latent heat recovered from condensing vapor may be used to boil the brine to precipitate some salt and remove some water (in the form of water vapor) from the brine. The remaining potash-concentrated brine may then be cooled to precipitate potash from the solution. The precipitated potash may then be further processed for final use.

Abstract: Process for producing sodium carbonate and sodium bicarbonate in a continuous mode out of trona comprising: c) feeding crushed trona, an extraction water and an additive in a first leaching tank containing a dissolution solution comprising sodium carbonate and sodium bicarbonate, wherein the additive is selected from the group consisting of: anionic hexametaphosphate, anionic polyphosphate, anionic polyphosphonate, soja lecithine, anionic polycarboxylate polymer, anionic polyacrylate polymer, anionic polyacrylate-polyacrylamide co-polymer, anionic hydrolyzed polymaleic polymers, anionic maleic-acrylic acids copolymers, anionic acrylic acid-phosphonic acid copolymers and combinations thereof; d) dissolving at least partially the crushed trona in the dissolution solution in order to produce a first suspension; e) removing continuously the first suspension from the first leaching tank and feeding it with an additive into a second leaching tank wherein the additive is selected from the same group of additives of

Abstract: Process for the combined regeneration of at least two soluble salts contained in a residue of an industrial process comprising heavy metals, comprising: adding an amount of reactive aqueous solution needed to completely dissolve the salts which are desired to be regenerated to the residue; subjecting the resulting aqueous suspension to a separation to obtain an aqueous production solution on the one hand and insoluble impurities on the other hand, which are removed; successively subjected the aqueous production solution to at least two selective crystallization steps intended to crystallize, separately, the at least two soluble salts which are desired to be regenerated, which are washed, dried and regenerated separately; and adjusting the concentration of at least one of the soluble salts to be regenerated in the aqueous production solution, at the moment when such solution is subjected to the step of crystallization of this salt, to give rise to the selective crystallization of this salt, by addition of a co

Abstract: Disclosed are a recovery for a metaloxidic cathodic active material for a lithium ion secondary battery and a synthesis thereof by the recovery method, wherein the recovery method includes (a) dissolving a cathodic active material from a waste lithium ion secondary battery using sulfuric acid solution containing sulfurous acid gas to generate a solution containing metal ions, (b) injecting sodium hydroxide solution and ammonia solution in the solution containing the metal ions to fabricate an electrode active material precursor, and (c) filtrating the active material precursor, followed by drying and grinding, thus to fabricate a solid-state cathodic active material precursor, and the synthesis method is achieved by mixing the electrode active material precursor fabricated according to the recovery method with lithium carbonate or lithium hydroxide, followed by heat treatment, to generate a metaloxidic cathodic active material.

Abstract: A material with cationic exchanger properties is introduced into aqueous media, where the equilibriums of carbon dioxide dissolution take place. A cationic exchanger material x/nM+nEx? is used to capture hydronium cations (H3O+) according to: x/nM+nEx?(s)+xH3O+(aq)=xH3O+Ex?(s)+x/nM+n(aq) where “x” stands for molar amount of the anionic centers of charge of the cationic exchanger material Ex? balanced by x/n molar amount of metal M, “n” stands for the metal valence, and M is selected from the group consisting of 1A and/or 2A of the periodic table of elements. This capture of the hydronium cations, H3O+, shifts certain reaction equilibriums to the right, according to Le Chatelier's principle, producing more bicarbonate, HCO3?, and/or carbonate, CO3=, than would otherwise be obtained.

Abstract: Aspects of the present invention relate to a process to obtain potassium chloride that includes submitting brine to concentration, separating brine after concentration, resulting in a first solid content and a first liquid content, cooling the first liquid content, separating the first liquid content after cooling, thus resulting in a second solid content and a second liquid content, enriching the second solid content, and separating the second solid content after enrichment, thus resulting in a third solid content and a third liquid content. Aspects of this process are environmentally safe, as the process includes stages using solvents and equipment which does not harm the environment. Moreover, aspects of this process present a significant energy consumption reduction.

Abstract: A method for removing impurities from a waste solid to provide at least a portion of a suitable crystallizer feed to a process for making crystalline sodium carbonate, bicarbonate, and/or other derivatives. The method comprises: contacting the waste solid with a leach solution to dissolve at least one impurity and dissolving the resulting leached residue. Leaching may include heap percolation. The leach solution may comprise a crystallizer purge liquor, a process waste effluent, a mine water, or mixtures thereof. The method may further comprise adding a magnesium compound to the resulting leached residue during or after its dissolution to remove another impurity. The waste solid preferably comprises a pond solid containing such impurities. The pond solid may be recovered from a pond receiving crystallizer purge liquor(s) and/or other process waste effluent(s). The pond solid may contain sodium carbonate, any hydrate thereof, sodium bicarbonate, and/or sodium sesquicarbonate.

Abstract: Disclosed are a method of producing fine particulate alkali metal niobate in a liquid phase system, wherein the size and shape of the particulate alkali metal niobate can be controlled; and fine particulate alkali metal niobate having a controlled shape and size. One of specifically disclosed is a method of producing a substantially rectangular cuboid particulate alkali metal niobate represented by MNbO3 (1), wherein M represents one element selected from alkaline metals, including specific four steps. Another one of specifically disclosed is particulate alkali metal niobate represented by the formula (1) having a substantially rectangular cuboid shape, wherein the substantially rectangular cuboid shape has a longest side and a shortest side, the length of the longest side represented by an index Lmax is 0.10 to 25 ?m, and the length of the shortest side represented by an index Lmin is 0.050 to 15 ?m.

Abstract: A potash-extraction system and method for extracting potash from a brine containing potash without the use of water-consuming evaporation ponds or additional chemicals is disclosed. The potash processing system uses a vapor-compression cycle (e.g., heat pump or refrigeration system) to separate potash from brine containing potash and NaCl. In embodiments, heat emitted by components of the vapor-compression cycle (e.g., condenser heat exchanger, evaporator heat exchanger) may heat the brine to precipitate some NaCl from the brine. The remaining potash-concentrated brine may then be cooled to precipitate potash from the solution. The precipitated potash may then be further processed for final use.

Abstract: A process for the production of sodium carbonate and sodium bicarbonate out of trona, comprising crushing trona ore and dissolving it in a leaching tank containing a solution comprising sodium carbonate and sodium bicarbonate, and an additive selected from the group consisting of: phosphates, phospholipids, carboxylates, carboxilic acids, and combinations thereof, saturated in sodium bicarbonate, in order to produce solid particles suspended in a production solution comprising sodium carbonate, the solid particles containing insoluble impurities and at least 65% by weight of sodium bicarbonate. The solid particles are separated from the production solution containing sodium carbonate. At least part of the production solution containing sodium carbonate is taken out of the leaching tank.

Abstract: An aqueous solution containing an alkali metal compound solute and organic compound contaminants may be treated with ozone to oxidize and/or dissolve the organic contaminants. Treating the aqueous solution with ozone may decrease color contaminants in the alkali metal compound and may also decrease foaming in subsequent crystallization of the alkali metal compound.

Abstract: A preparation method of lithium carbonate, in recovering valuable resources of a lithium-ion battery, reducing impurities from lithium carbonate, having a pretreatment process, comprising: a first step cleaning an organic phase containing nickel and lithium prepared by a solvent extraction by use of a sulfuric acid solution containing nickel and enriching lithium in the cleaning solution; a second step extracting a residual nickel only by an organic solvent from a post-cleaning solution in which the lithium is enriched; and a third step controlling pH of the post-extraction solution containing the lithium by ammonia water or lithium hydroxide.

Abstract: A process for formulating high purity potassium chloride from a carnallite source. The process takes advantage of solubility differences and saturation levels in a multiple salt system generated upon dissolution of carnallite. In the system, the sodium chloride is kept in solution and the magnesium chloride present in the system is controlled to be in a concentration range of between 12% and 25% by weight. This avoids co-precipitation of sodium chloride with the potassium chloride during crystallization and therefore prevents the sodium chloride from contaminating the potassium chloride. The result is high grade potassium chloride.

Abstract: Process for the combined regeneration of at least two soluble salts contained in a residue of an industrial process comprising heavy metals, comprising: adding an amount of reactive aqueous solution needed to completely dissolve the salts which are desired to be regenerated to the residue; subjecting the resulting aqueous suspension to a separation to obtain an aqueous production solution on the one hand and insoluble impurities on the other hand, which are removed; successively subjected the aqueous production solution to at least two selective crystallization steps intended to crystallize, separately, the at least two soluble salts which are desired to be regenerated, which are washed, dried and regenerated separately; and adjusting the concentration of at least one of the soluble salts to be regenerated in the aqueous production solution, at the moment when such solution is subjected to the step of crystallization of this salt, to give rise to the selective crystallization of this salt, by addition of a co

Abstract: The disclosed technology relates to a dispersion comprising LiOH and/or LiOH.H2O particulates dispersed in an organic medium comprising at least one oil and at least one surfactant, the concentration of LiOH and/or LiOH.H2O particulates in the dispersion being greater than 10% by weight, the LiOH and/or LiOH.H2O particulates having a mean particle size in the range up to about 10 microns wherein at least about 99% by weight of the LiOH particulates have a particle size in the range up to about 20 microns. A process for making the dispersion is disclosed. Grease compositions made using the dispersion are disclosed.

Abstract: The present invention generally relates to processes for recovery of phosphorus values and salt impurities from aqueous waste streams. In particular, the present invention relates to processes for recovery of phosphorus values and salt impurities from aqueous waste streams generated in the manufacture of phospho-herbicides, including N-(phosphonomethyl)glycine and glufosinate.

Abstract: Provided herein are processes for obtaining sylvinite and/or sylvite from sea water, sea bitterns and/or sea salts. The processes comprise reacting sea water, sea bitterns and/or sea salts with calcium hydroxide and/or calcium oxide.

Abstract: A method for removing impurities from a waste solid to provide at least a portion of a suitable crystallizer feed to a process for making crystalline sodium carbonate, bicarbonate, and/or other derivatives. The method comprises: contacting the waste solid with a leach solution to dissolve at least one impurity and dissolving the resulting leached residue. Leaching may include heap percolation. The leach solution may comprise a crystallizer purge liquor, a process waste effluent, a mine water, or mixtures thereof. The method may further comprise adding a magnesium compound to the resulting leached residue during or after its dissolution to remove another impurity. The waste solid preferably comprises a pond solid containing such impurities. The pond solid may be recovered from a pond receiving crystallizer purge liquor(s) and/or other process waste effluent(s). The pond solid may contain sodium carbonate, any hydrate thereof, sodium bicarbonate, and/or sodium sesquicarbonate.

Abstract: The process of the invention is an improvement over the existing process of producing salt of high purity from alum-treated brine disclosed recently in the prior art. More particularly, the invention rectifies the ratio of Ca2+ to Mg2+ from a value <1 to a value in the range of 2-3 desired by chlor-alkali and soda ash industries. The improved process involves the adjustment of pH of clarified brine with aqueous HCl so as to carry out salt crystallization at a pH of 6.5 instead of at the natural pH of 7. The pH adjustment reduces the Mg2+ impurity in salt while slightly raising the Ca2+ impurity in the salt and thereby achieving the desired ratio.

Abstract: This invention relates to a method for producing chromates, especially for producing alkali metal chromates. The method comprises following steps: the obtaining of a mixture of alkali metal hydroxide, alkali metal chromate, and ferrous residue after the reaction of chromite ore with an oxidant in the reactor in the presence of molten salt or in aqueous solution of alkali metal hydroxide, the obtaining of a leaching slurry by leaching the reaction products with aqueous solution of alkali metal hydroxide, the separating of the primary chromate product from the leaching slurry, the obtaining of pure chromate crystal by purifying the primary chromate product. Both the primary chromate product and the pure chromate crystal can be used as the raw materials to manufacture other chromium compounds. Compared with the currently-used roasting method, the method has the advantages of decreasing the reaction temperature by about 700° C.

Abstract: Processes are described for the extraction and recovery of alkali metal from the char that results from catalytic gasification of a carbonaceous material. Among other steps, the processes of the invention include a hydrothermal leaching step in which a slurry of insoluble particulate comprising insoluble alkali metal compounds is treated with carbon dioxide and steam at elevated temperatures and pressures to effect the conversion of insoluble alkali metal compounds to soluble alkali metal compounds. Further, processes are described for the catalytic gasification of a carbonaceous material where a substantial portion of alkali metal is extracted and recovered from the char that results from the catalytic gasification process.

Abstract: Processes are described for the extraction and recovery of alkali metal from the char that results from catalytic gasification of a carbonaceous material. Among other steps, the processes of the invention include a hydrothermal leaching step in which a slurry of insoluble particulate comprising insoluble alkali metal compounds is treated with carbon dioxide and steam at elevated temperatures and pressures to effect the conversion of insoluble alkali metal compounds to soluble alkali metal compounds. Further, processes are described for the catalytic gasification of a carbonaceous material where a substantial portion of alkali metal is extracted and recovered from the char that results from the catalytic gasification process.

Abstract: Embodiments of the invention provide a system and process for recovering useful compounds from a byproduct composition produced in a silicon tetrafluoride production process.

Abstract: The invention pertains to removing soluble alkali metal or ammonium salt of a divalent anion from brine comprising following steps: obtaining brine with NaCl-concentration between 150g/L and saturation in the presence or absense of a cyrstal growth inhibitor for NaCl(GCI-NaCl),or with NaCl concentration above saturation in the presence of a CGI-NaCl, said brine optionally comprising a crystal growth inhibitor for the alkali metal or ammonium salt of the divalent anion(CGI-DA); if necessary, acidify the solution to pH<11.5; if the concentration of CGI-DA is less than 20 mg/L, adding CGI-DA to obtain at least 20 mg CGI-DA/L; subjecting the solution to a membrane filtration; if the concentration of CGI-DA in the concentration from the separation is less than 20 mg/L, adding CGI-DA to obtain at least 20 mg CGI-DA/L; crystalling the concentration; removing the crystallized alkali metal or ammonium salt of the divalent anion.

Abstract: Disclosed is an alkali aqueous flocculating agent based on an alkali aqueous salt clay extract containing dissolved silicate and aluminate, in addition to alkali chloride whereby for an aluminate (1) content by weight expressed as Al(OH)3, 1.) approximately 2 to 3 parts by weight of silicate expressed as SiO2 are provided and 2) at least approximately (10) parts by weight, especially at least (20) parts by weight of alkali chloride are provided, in addition to a flocculating and a sedimentation agent in the form of an acidic and alkali-extracted salt clay. The invention further relates to a method for the production of said flocculating and sedimentation agents which can be used advantageously in swimming baths, for the treatment of drinking water, industrial water, grey water and waste water in sewage treatment plants as auxiliary agents for absorption, sedimentation and filtration.

Abstract: A magnesium treatment for removing water-soluble impurities in a process for making crystalline sodium carbonate, bicarbonate, or sulfite. A waste comprising such impurities is treated with a magnesium compound to form water-insoluble matter which is removed to form a purified solution. The treatment may be performed on a solution which contains the waste and optionally dissolved calcined trona. The purified solution may be used as a feedstock to form crystalline soda ash, and/or used as a reactant to produce crystalline sodium sulfite or bicarbonate via reaction with SO2 or CO2. In preferred embodiments, the waste may comprise a purge or weak liquor, a reclaimed solid, or combinations thereof. The water-soluble impurities may be silicates and/or foam-causing impurities, and the waste may contain sodium bicarbonate, sodium sesquicarbonate, and/or one or more sodium carbonate hydrates, such as decahydrate.

Abstract: An aqueous solution containing an alkali metal compound solute and organic compound contaminants may be treated with ozone to oxidize and/or dissolve the organic contaminants. Treating the aqueous solution with ozone may decrease color contaminants in the alkali metal compound and may also decrease foaming in subsequent crystallization of the alkali metal compound.

Abstract: A method is disclosed for separating trivalent americium from trivalent curium, coming from an aqueous solution containing at least these cations, wherein, at an acid concentration of 0.01 mol/l-0.3 mogl/l, the aqueous solution is brought into contact with an organic solvent containing a bis(aryl)dithiophosphinic acid having the formula (4) where R1=phenyl or naphthyl R2=phenyl or naphthyl, and radicals of R1 and R2 substituted by at least one methyl, ethyl, propyl, isopropyl-, cyano, nitro, or halo substituent, and containing a synergist having the formula (5) where X and/or Y and/or Z is R or RO, wherein R is branched or unbranched alkyl.

Abstract: Disclosed is a process for recovery of uranium from a spent nuclear fuel using a carbonate solution, characterized by excellent proliferation resistance of preventing leaching of transuranium element (TRU) nuclides such as Pu, Np, Am, Cm, etc. from the spent nuclear fuel as well as environmental friendliness of minimizing waste generation, wherein a highly alkaline carbonate solution is used to separate uranium alone from the spent nuclear fuel.

Abstract: The process of the invention deals with significant improvements in salt purity and whiteness brought about through treatment of brine with alum prior to charging into crystallizers for solar salt production. The improvements realized are partly on account of elimination of suspended impurities like gypsum and clayey matter in the brine, which may otherwise be carried along with the brine in the crystallizer and finally end up in the salt, and partly due to the improved crystal size and morphology that minimizes embedded impurities in the salt. Rain washing of the heaped salt has resulted in a salt with greatly reduced calcium and sulphate impurity levels hitherto not achieved in solar salt production. Alum treatment by the process of the invention requires no additional time or infrastructure and the cost of the treatment works out to <3 U.S. cents per ton of salt. The process can be implemented in any solar salt works.

Abstract: A process and an apparatus are described for treating seven types of saline waters each having a concentration of total dissolved solids exceeding 1 g/L, wherein the concentration of total dissolved solids, the ratio of the chloride ion concentration to the bicarbonate ion concentration and the ratio of the chloride ion concentration to the sulphate ion concentration of each of the water types are as indicated in Table 1. The process includes the steps of contacting the water with a first reagent comprising a source of calcium ions selected from calcium oxide and calcium hydroxide to form a first solid product which is recovered. The process includes a further step of subjecting at least a portion of the partially processed water to at least partial evaporation so as to promote the formation of a precipitate and a mother liquor. The precipitate is recovered as a second product.

Abstract: A process related to sodium chemicals production, including the processing of bicarbonate containing solutions obtained by solution mining of trona, nahcolite or wegscheiderite reserves and the lake waters containing bicarbonates, includes the steps of purification, evaporation-decarbonation, crystallization, centrifuging, and drying.

Abstract: A method for producing sodium hydrogencarbonate crystal particles having a low caking property, which comprises lowering the potassium concentration in sodium hydrogencarbonate crystal particles having a mean particle diameter of from 50 to 500 ?m to a level of at most 50 mass ppm.

Abstract: A method for recovering at least one metallic element from ore or other material is described and includes reacting ore or other material with a salt capable of recovering the metallic element from the ore or other material to form a reaction product that includes the metallic element. The method also includes recovering the metallic element from the reaction product. To remove the metallic element from the reaction product, the method can involve crushing the reaction product to form a crushed material and dissolving the crushed material in a solvent to remove the precipitates, thereby leaving a sulfate solution containing the metallic element.

Abstract: Feeding device for feeding burned lime to a reaction vessel for causticizing a soda liquor to caustic soda. The feeding device, in its upper part, comprises an inlet for a slurry of the burned lime and the soda liquor for formation of said slurry inside said feeding device. The system further comprises a tall and slender feed vessel having a lower part having an outlet defined therein for the slurry. The outlet, via a pump, is operatively connected to the reaction vessel. The process and the feeding system utilize the feeding device, in which process the slurry is created of the burned lime and a first part of the soda liquor, a second part being preheated before addition to the slurry, whereafter slaking and causticizing reactions are completed under elevated temperature and pressure.

Abstract: It is provided that a method for preparing disodium paraperiodate, characterized in that a pH of a reaction mixture which is obtained by reacting sodium iodate, iodic acid or a mixture thereof with sodium hypochlorite using sodium hydroxide is adjusted to the range between 5 and 10.

Abstract: Provided is a cathode composition for lithium secondary battery that includes a lithium-chromium-titanium-manganese oxide that has the formula Li[Li(1-x)/3CrxTi(2/3)yMn2(1-x-y)/3]O2 where 0?x?0.3, 0?y?0.3 and 0.1?x+y?0.3, and layered a-LiFeO2 structure. A method of synthesizing the lithium-chromium-titanium manganese oxide includes preparing a first mixed solution by dispersing titanium dioxide (TiO2) in a mixed solution of chrome acetate (Cr3(OH)2(CH3CO2)7) and manganese acetate ((CH3CO2)2Mn.4H2O), adding a lithium hydroxide (LiOH) solution to the first mixed solution to obtain homogeneous precipitates, forming precursor powder that has the formula Li[Li(1-x)/3CrxTi(2/3)yMn2(1-x-y)/3]O2 where 0?x?0.3, 0?y?0.3 and 0.1?x+y?0.3 by heating the homogeneous precipitates, and heating the precursor powder to form oxide powder having a layered structure.

Abstract: The present invention is directed to a novel integrated process for the recovery of sulphate of potash (SOP) from sulphate rich bittern. The process requires bittern and lime as raw materials. Kainite type mixed salt is obtained by fractional crystallization of the bittern, and is converted to schoenite which is subsequently reacted with muriate of potash (MOP) for its conversion to SOP. End liquor from kainite to schoenite conversion (SEL) is desulphated and supplemented with MgCl2 using end bittern generated in the process of making carnallite. Decomposed carnallite liquor produced is reacted with hydrated lime for preparing CaCl2 solution and high purity Mg(OH)2 having low boron content. It is shown that the liquid streams containing potash are recycled in the process, and the recovery of potash in the form of SOP is quantitative.

Abstract: This invention relates to methods and installations for producing ultra pure sodium chloride salt crystals primarily for use in saturating depleted brine resulting from the electrolytic decomposition of saturated brine in chlor alkali membrane cells for the production of chlorine, caustic soda and hydrogen. More particularly, this invention relates to the production of ultra pure sodium chloride salt crystals by processing primary treated brine by first acidifying the primary treated brine, then stripping the carbonic acid produced by acidification as carbon dioxide, and then returning the brine to a pH of about 6 or higher which is sufficient for processing it in evaporation equipment where the ultra pure salt crystals are produced.

Abstract: A low temperature contaminant limiting process for lithiating hydroxides and forming lithiated metal oxides of suitable crystalinity in-situ. M(OH)2 is added to an aqueous solution of LiOH. An oxidant is introduced into the solution which is heated below about 150° C. and, if necessary, agitated. M may be selected from cobalt, nickel and manganese. The resultant LiMO2 becomes crystallized in-situ and is subsequently removed.

Abstract: The present invention relates to recovery of industrial grade potassium chloride and low sodium edible salt from bittern as part of an integrated process. The process comprises, mixing low sulphate concentrated feed bittern (a by-product of salt industry) of density 31.5 to 32.5° Be (sp.gr. 1.277–1.289) with high density end bittern of density 36.5 to 37.5° Be? (sp.gr. 1.336–1.35), thereby producing low sodium carnallite, from which industrial grade potassium chloride is produced. The resultant bittern is evaporated in forced evaporation system, thereby producing crude carnallite, from which low sodium salt that would be beneficial to persons suffering from hypertension is produced. When sulphate-rich bittern is used, such bittern is desulphated with CaCl2 that is generated from carnallite decomposed liquor through reaction with lime, and wherein low B2O3-containing Mg(OH)2 is a by-product. The entire content of potassium in feed bittern is recovered in the process of the invention.

Abstract: The present invention relates to an improved process for obtaining sodium silicate alkali solution depleted of sodium salt and enriched in silica from a mother liquor recovered after isolation of molecular sieves and more particularly, the present invention relates to a process for recycling mother liquor obtained after the isolation of molecular sieves for the preparation of fresh molecular sieves or as a binder for producing Fluid Catalytic Cracking (FCC) catalyst.

Abstract: A system and method for removing a by-product from a chemical hydride solution is disclosed. The method includes the steps of: (a) withdrawing the chemical hydride solution at a first temperature from the reactor; (b) cooling the chemical hydride solution to a second temperature below the first temperature, wherein a precipitate is formed from a portion of the by-product; (c) removing the precipitate from the chemical hydride solution; (d) heating the chemical hydride solution to a third temperature above the second temperature, to dissolve the remaining precipitate; and (e) delivering the chemical hydride solution back to the reactor.

Abstract: A method for producing sodium bicarbonate from a nahcolite deposit comprising injecting water or other aqueous solution at a temperature of at least 250° F. into the deposit, dissolving sodium bicarbonate in the hot water to form a production solution and subjecting the production solution to multiple stages of crystallization. The sodium bicarbonate crystals may be dewatered and dried to form a commercial sodium bicarbonate product.

Abstract: Novel iron sulfides having excellent durability and excellent treating properties of heavy metals, processes for producing the iron sulfides, iron sulfide mixture, a heavy metal treating agent containing either of these novel iron sulfides as an effective component, and a method by which wastes containing various heavy metals are treated with the heavy metal treating agent are disclosed. The iron sulfide having a mackinawite structure which contains FeMxNySz wherein M represents an alkaline earth metal, N represents an alkali metal, and x, y and z, indicating the molar proportions of the respective elements, represent numbers satisfying 0.01<x≦0.5, y≦0.2 and 0.7≦z≦1.4, as an essential component.