Abstract: The present invention relates to a device for efficiently preparing magnesium hydroxide, comprising a material mixing tank, a coordinated pressure control unit I, a reactor, a coordinated pressure control unit II, a condenser, a three-way valve, a material storage tank, a coordinated pressure control unit III and a steam generator.

Abstract: The present invention relates to a process for the preparation of precipitated calcium carbonate comprising the steps of a) providing and calcining calcium carbonate comprising material; b) slaking the reaction product obtained from step a) with an aqueous ammonium chloride solution; c) separating insoluble components from the calcium chloride solution obtained from step b); d) carbonating the calcium chloride solution obtained from step c); e) separating the precipitated calcium carbonate obtained from step d); the precipitated calcium carbonate obtained by this process, as well as uses thereof.

Abstract: Provided are methods for recovering phosphate from wastewater by treating the wastewater with calcium containing compounds to raise its pH to near neutral values in order to precipitate calcium phosphate compounds, such as brushite, from the wastewater.

Abstract: Methods and apparatus for precipitating dissolved materials from a solution involve reduction of fines. In an embodiment, the method comprises: introducing a solution into a reactor, causing the dissolved materials in the solution to precipitate into crystals under a first reaction condition, adjusting the reaction condition from the first reaction condition to a second reaction condition, maintaining the reaction condition in the second reaction condition to cause a sub-population of the crystals to dissolve, and adjusting the reaction condition from the second reaction condition to the first reaction condition. In an embodiment, the apparatus comprises a reaction tank, a recycling path and at least an acid injector which is configured for dosing an acid into solution flow in the recycling path.

Abstract: An object of the present invention is to provide a fine crystal particle production method and device that are excellent in mixing efficiency. This object is achieved by a method for producing fine crystal particles, comprising: a swirl flow producing step at which a swirl flow of liquid a comprising reactant A is supplied into a cylinder having a circumferential surface partially or wholly composed of a porous membrane; and a reaction step at which liquid b comprising reactant B which is reactive with the reactant A is supplied through the porous membrane to the swirl flow to effect mixing, whereby the reactants A and B are reacted to precipitate fine crystal particles.

Abstract: In one embodiment, a method for producing a naturally purified salt product such as magnesium sulfate heptahydrate, wherein the salt mixture is treated with a solution comprising magnesium chloride; the first slurry is separated to provide a second slurry, which is further separated to yield a first liquid stream; the first liquid stream is crystallized to provide the naturally purified salt product. In another embodiment, a high purity salt product is produced. In another embodiment, other products that are produced include naturally purified sodium chloride and magnesium chloride.

Abstract: Mineral, cosmetic, pharmaceutical, agricultural, nutraceutical, and other compositions are produced using a mineral composition containing minimal concentrations of cadmium, lead, arsenic, and mercury and containing relatively high concentrations of micro and macro mineral elements, of rare earth elements, of calcium, and of silica. The mineral concentrations are produced by processing naturally occurring clay soil to concentrate mineral elements naturally occurring in the soil.

Abstract: This invention refers to a novel process to obtain magnesium hydroxide and sodium sulfate from a solid raw material, which contains sodium and magnesium soluble salts, preferably in the form of sulfates, coming from a natural source or as a byproduct of an industrial process. The process consisting in the conditioning of the raw material to guarantee the correct concentrations of sodium and magnesium sulfates that is subjected to a salting-out crystallization when mixed with sodium sulfate obtaining sodium sulfate; the resulting solution is subjected to an alkali treatment to precipitate the magnesium hydroxide and the mother liquor is fed to a regeneration stage of the alkali used in the precipitation of the magnesium hydroxide as well in the sodium sulfate solution for the crystallization. The crystallization can be performed as a multistage process countercurrent to increase the purity of sodium sulfate.

Abstract: The present invention provides a method of crystallizing Yb:C-FAP [Yb3+:Ca5(PO4)3F], by dissolving the Yb:C-FAP in an acidic solution, following by neutralizing the solution. The present invention also provides a method of forming crystalline Yb:C-FAP by dissolving the component ingredients in an acidic solution, followed by forming a supersaturated solution.

Abstract: An objective of the present invention is to provide a method of atomizing a substance poorly soluble in carbon dioxide in a supercritical state. The present invention relates to a method of atomization comprising: introducing a substance which is difficult to be atomized by use of only carbon dioxide in a supercritical state, water and carbon dioxide into a pressure vessel; applying heat and pressure to an interior of the pressure vessel to bring the carbon dioxide into a supercritical state; and returning a pressure of the interior to normal pressure.

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: The present invention provides a method for stabilizing fine particles of calcium phosphates without lowering their solid phase forming activity. It is possible to stabilize the fine particles of calcium phosphates by stopping the growth of the fine particles formed in an aqueous solution supersaturated with respect to calcium phosphates. More specifically, the fine particles of calcium phosphates were stabilized by lowering the inorganic ion concentration of a fine-particle-forming solution containing fine particles of calcium phosphates by dialysis, ion exchange, dilution, or the like, or by separating the fine particles of calcium phosphates from the fine-particle-forming solution by filtration, centrifuging, or the like.

Abstract: The present invention describes a process for treating phosphogypsum and in particular the related leachate that comprises the steps of feeding a continuous leachate flow with a dry content of below 5% by weight into a concentration unit heated to a predetermined temperature and equipped with dedicated mixing means, and continuously discharging a concentrated leachate flow having a dry content comprised between 20% and 95% by weight from the concentration unit.

Abstract: Neutral calcium-aluminum double salts of the formula (A): Ca2m(Zn2n)Al2(OH)6+2(2m+2n?1)An*oH2O??(A), where the following apply for m and n:m=0.5 to 3 and 0.5m?n>0; An=CO3, where this may be replaced completely or partially by at least one of the following groups selected from OH, ClO4 and H3CS(?O)2O (triflate) and o=0 to 3. The present invention further relates to their preparation, use in compositions and stabilizer systems and uses thereof.

Abstract: Methods for producing naturally purified salt products are disclosed. In one embodiment, a method of producing a naturally purified salt product such as magnesium sulfate heptahydrate from a salt mixture is disclosed. In another embodiment, a high purity salt product is produced. In another embodiment, other products that are produced include naturally purified sodium chloride and magnesium chloride.

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: Processes for the preparation, concentration and recovery an N-(phosphonomethyl)glycine product from aqueous process streams including contacting mother liquor generated in the precipitation of N-(phosphonomethyl)glycine product crystals with a selective membrane to produce a retentate enriched N-(phosphonomethyl)glycine product and a permeate depleted in N-(phosphonomethyl)glycine product are disclosed.

Abstract: There is provided a low sodium sea salt and a method for producing the same. A first amount of natural seawater containing sodium, chloride, potassium, magnesium, sulfate and other trace minerals is introduced into a containment structure which is periodically exposed to the sun. Preferably, the containment structure is located outdoors in an arid climate with direct exposure to sunlight. An amount of water is evaporated forming a brine. An amount of sodium chloride is crystallized and an amount of the crystallized sodium chloride is removed so that the remaining brine includes substantial amounts of potassium, magnesium and sulfate. A second amount of natural seawater is combined with the remaining brine forming a diluted brine. An amount of water is evaporated from the diluted brine. Sodium chloride, potassium sulfate and magnesium sulfate is crystallized forming a low sodium sea salt whereby the sodium chloride is no more than 70 weight percent.

Abstract: A process to regenerate wet flue gas scrubber purge liquid into NaOH caustic suitable for make-up caustic for the scrubber is disclosed. Further, sulfur is removed from waste effluent in the form of gypsum with the process described herein. Lime is added to the spent, sodium sulfate-containing purge liquid to result in the formation of gypsum and sodium hydroxide.

Abstract: The invention is directed to a process for recovering a crystalline material from an aqueous solution, which solution also contains organic contaminants, in which process the material is crystallised from the aqueous solution by freeze crystallising at a eutectic freezing point of the solution.

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: A method and apparatus for continuous fabrication of homogeneous thin flake or powder electrolyte material from inorganic salt, metallic or similar materials or from mixtures of such materials for use in Carbonate Fuel Cell (“CFC”) power plants. Electrolyte precursor powders are fed to a continuous blender type mixer using precision metering equipment that controls material feed rates. The homogenous mixture of blended powders is then fed into a high temperature melting tank in which the mixture is melted, forming the desired molten eutectic composition. The liquid eutectic melt drips from the melting tank through ceramic or metallic nozzles and splat-cools on a rotating, water-cooled metal cylinder to produce uniform size, thin flake material. The thin flake electrolyte material can be used as-is, or it may be further processed using continuous grinding and powder fabrication equipment.

Abstract: A composition for reducing deposition of a mineral salt from an aqueous supersaturated solution onto a solid surface in contact with the aqueous supersaturated solution which composition comprises a dispersion of either (i) seed crystals of the mineral salt in an aqueous solution of the mineral salt or (ii) seed crystals of a salt isomorphous with the mineral salt in an aqueous solution of the isomorphous salt wherein the dispersed seed crystals are of Mean particle size of less than 2.5 microns.

Abstract: Process for recycling a composition comprising pulverulent calcium fluoride in the form of micrometric particles comprising: (i) a stage of mixing, in the presence of water, the said composition with pulverulent calcium fluoride (also known as natural spar), the particle size of which is suitable for feeding an HF furnace, in a ratio r of less than 75% by weight, preferably of less than 30%, then (ii) a stage of drying the mixture resulting from (i) until a residual water content is obtained which is also suitable for feeding an HF furnace; the stage (ii) optionally being carried out simultaneously with the stage (i).

Abstract: Process of crystallization of sodium bicarbonate from solution mined Nahcolite pregnant liquor comprising the use of from about 2 to 100 parts per million of lecithin, introduced full strength, made miscible in water with a soap or detergent, saponified with NaOH at a pH of 10-12, or preferably as a mixture of lecithin in pregnant or barren liquor containing HCO3−/CO3= ions at a pH in the range of from about 8 to 12, preferaby 8-10. The lecithin functions as a crystal growth modifier, producing improved crystal yields, product size classification, improved crystal shape including reduction in dendritic, branched and twinned forms, very significant scale reduction, reduction in wet cake moisture, increase in product bulk density, reduction in both oversize and undersize fractions (the classification phenomenon) and less breakage during drying and handling.

Abstract: There is described a method for the treatment and processing of solutions of an organic fluid, water and one or more compounds of alkaline earth metals, alkali metals and metal ions, comprising the following steps: a) conducting a stream (5) consisting of organic fluid, water and one or more compounds of alkaline earth metals, alkali metals and metals ions to a salt reduction and crystallization unit (6), b) evaporating and optionally partially condensing the stream (5) and providing thereby a steam (9, 10) of evaporated water and organic solvent and a steam (8) of organic fluid and the compounds of alkaline earth metals, alkali metals and/or metal ions, c) conducting the steam (8) consisting substantially of organic fluid and the compounds of alkaline earth metals, alkali metals and/or metals ions to a salt reduction means (24), d) nucleating crystals of the compounds of alkaline earth metals, alkali metals and/or metal ions by means of depressurization and temperature increase, e) removing the portion of th

Abstract: The present invention relates to a process for the manufacture of particles comprising magnesium chloride, which may serve as a support for a catalytic component for the polymerization of olefins, this process comprising a step of placing in contact between solid particles, an organomagnesium derivative and a chlorinating agent for the organomagnesium derivative. The process affords excellent control over the morphology of the support particles, particles of catalytic component and polymer particles.

Abstract: Low-cost, high-purity strontium nitrate that is low in Ba, Na, Ca, Cr, and other impurities and that is suitable for use in airbags or the like is provided. High-purity strontium nitrate having a Ba content of 0.01 wt % or lower, an Na content of 0.005 wt % or lower, a Ca content of 0.01 wt % or lower, a Cr content of less than 0.001 wt %, and a purity of 99.5 wt % or higher is produced by a manufacturing method comprising a first step for performing crystallization by adding nitric acid to an aqueous solution obtained by dissolving a strontium compound as a starting material, a second step for separating the resulting crystals, a third step for crystallizing the resulting separated solution, and a fourth step for separating the resulting crystals.

Abstract: The invention relates to a method for the manufacture of an electrolyte and acetic acid granulate for making a hemodialysis solution, the granulate comprising the electrolytes potassium chloride, calcium chloride and magnesium chloride, and the method comprising preparing the granulate and adding a desired quantity of acetic acid. The granulate, which is easy to process and has free flow capability, is made by crushing the electrolyte salts to a grain size of less than 0.5 mm and subsequently granulating the electrolyte salts in a dry gas atmosphere to a granulate having a grain size of 1 to 10 mm and a pore volume of more than 25 percent by volume. Subsequently, the acetic acid is added to the granulate, preferably by spraying.

Abstract: In the method, calcium chloride scales (75) are produced on a cooled surface (20), namely through the application of a layer (70) consisting of an aqueous CaCl.sub.2 solution (7) to the cooled surface, solidification of the layer and stripping off the solidified layer. The solution contains less than 70% CaCl.sub.2 by weight, preferably less than 65% CaCl.sub.2 by weight. The layer thickness is set to a maximum of about 1 mm. A relative speed between the point of application of the solution and the cooling surface is produced so that a specific production rate of at least 20 g/s m.sup.2 is connected with this relative speed. The heat is carried off so rapidly through the cooling surface that the solidified layer remains largely free from calcium chloride dihydrate, CaCl.sub.2.2H.sub.2 O. Dry scales thus arise.

Abstract: Methods are disclosed in which first and second reactant salts and, optionally, a complexing agent are added to a non-aqueous reaction solvent to form a reaction system. The reactant salts, which are substantially soluble and reactive with each other in water to form a first crystallite of calcium carbonate, are present in the reaction solvent in relative amounts that are sufficient to form a desired amount of the calcium carbonate in the reaction system. The complexing agent, if present, is a crown ether or other cyclic or acyclic polydentate chelating agent that, in the reaction solvent, forms chelation complexes with at least one of the reactant salts. Reaction of the first and second reactant salts in the reaction solvent forms a second crystallite precipitate comprising crystals of calcium carbonate having a different habit or morphology from calcium carbonate crystals in the first crystallite that would otherwise be formable in water by reaction of similar amounts of the first and second reactant salts.

Abstract: The process for environmentally acceptable and economical recovery of chloride salts from hardening-shop used salts utilizing the steps of leaching of the used salt, detoxification of the cyanide and selective crystallization of the individual chloride salts. The process is characterized in that all the chloride salts that are present in the hardening-shop used salt are recovered in pure form.

Abstract: A method for producing a stabilized magnesium hydroxide slurry comprising physically deflocculating the magnesium hydroxide solids in a starting slurry to produce a stabilized magnesium hydroxide slurry. Depending on the chloride level of the starting slurry, a cationic polymer may be added to the slurry. Optionally a thickening agent may be added to the deflocculated slurry. Also disclosed is a stabilized magnesium hydroxide slurry produced by the method which may be transported and stored without substantial agglomeration of the magnesium hydroxide solids.

Abstract: Mineral salts, e.g., potassium chloride, are crystallized from aqueous solutions thereof in the presence of a crystal growth promoting amount of lecithin or lecithin containing compositions. Mineral salts include alkali metal and alkaline-earth metal chloride, sulfate, carbonate, phosphate and nitrate salts. The process is described as providing increased amounts of large crystals and a narrower and more uniform crystal size distribution.

Abstract: A flue-gas scrubbing-liquor regeneration process that is based on contacting N-S compounds contained in a flue-gas scrubbing liquor with a lime/limestone solution in a double draw-off crystallizer under suitable pH conditions for precipitating calcium salts of N-S compounds. The precipitated crop is filtered and then hydrolyzed in a sulfuric acid environment to produce gypsum and ammonium sulfate in solution. The hydrolyzed slurry is filtered and the filtrate is neutralized with lime to liberate ammonia gas that is then sparged through a sulfuric acid solution to cause the precipitation of commercial-grade ammonium sulfate.

Abstract: A generally dipyramidal-shaped catalyst precursor is prepared by dissolving magnesium dichloride and a suitable alcohol in a suitable solvent and then cooling to obtain a precipitate of the desired shape. The use of the precursor to prepare catalysts and the use of the catalysts to prepare polymers is also disclosed.

Abstract: An improved salt basket for dewatering solids, particularly salts resulting from evaporation of industrial wastewaters. The salt basket system includes a pressurizable vessel having a screen floor situated above a bottom liquid collection head, an inlet for the brine/solids slurry from which solids are to be separated and dried, an inlet for air, an inlet for steam (the latter two inlets may be combined, where convenient), an inlet for solids free feed, and a drain outlet (these two may be combined where convenient into a combination feed/drain connection). Preferably, an automated system for introducing feed brine and for removing the solids product is provided. For safety, a pivotally attached lower door has a hydraulic failsafe closure mechanism and locking safety latches to prevent the door from inadvertently opening.

Abstract: A method for producing a stabilized magnesium hydroxide slurry comprising physically deflocculating the magnesium hydroxide solids in a starting slurry to produce a stabilized magnesium hydroxide slurry. Depending on the chloride level of the starting slurry, a cationic polymer may be added to the slurry. Optionally a thickening agent may be added to the deflocculated slurry. Also disclosed is a stabilized magnesium hydroxide slurry produced by the method which may be transported and stored without substantial agglomeration of the magnesium hydroxide solids.

Abstract: A process for forming a microelement deficiency-corrector comprising a mixture of trace elements, in hydrated sulfate form, optionally containing carbonates and including iron, magnesium, manganese and zinc, with the following typical elemental analysis: Magnesium 3.5-6%; iron 12-19%; Manganese 11.5%; zinc 0.2-0.3% and organic matter 0-45%.The process comprises mixing 50-95% of the by-product of manufacture of titanium bioxide via sulfate, 5-10% alkaline earth carbonate or magnesite and, optionally, 10-45% organic matter, grinding the mixture, granulating it and drying it, cooling it and screening it.The corrector is used in agriculture to prevent and control ferric chlorysis, to favour physiological processes of harvests in which iron takes part and to avoid deficiencies of manganese and zinc farmland.

Abstract: Crystalline MgCl.sub.2 particulates, exhibiting the morphology of substantially regular polyhedra having an even number of from 10 to 18 face surfaces, are well suited as support substrate for olefin polymerization catalysts.

Abstract: The present invention is an improved method for crystallizing inorganic salts. The inorganic salts that are suitable for this process are characterized by the fact that they form isothermic or polythermic concave solubility curves. Each concave solubility curve represents saturated concentrations of the salt that is desired to be purified versus either concentrations of a second, different inorganic salt or versus temperature.

Abstract: A process for the manufacture of MgCl.sub.2.MgO with narrow granulometric distribution by treatment of hydrated MgCl.sub.2 with an alcohol followed by heat treatment after partial elimination of the alcohol, characterized in that the hydrated MgCl.sub.2 is suspended in the alcohol, and that the molar ratio of the alcohol to the hydrated MgCl.sub.2 is lower than the solutility ratio of these two substances at the temperature of the suspension. The resultant MgCl.sub.2.MgO can be employed as a support in catalytic components for the polymerization of olefins.

Abstract: A form of calcium carbonate having a blocky rhombohedral crystal structure and properties including a surface area of from about 3 to about 15 m.sup.2 g, an average discrete particle size of from about 0.2 to about 0.9 micron, wherein the discrete particles have an aspect ratio less than about, 2:1 and a particle size distribution such that at least about 60 weight percent of the particles have a size within 50 percent of the equivalent discrete particle spherical diameter, suitable for use as a filler material in papermaking to improve the optical properties of the resulting paper, is disclosed. An accelerated heat-aging process, including embodiments thereof which utilize hydrothermal techniques, for rapidly producing this form of calcium carbonate, and a related form of calcium carbonate having a hexagonal prismatic crystal structure and the same properties, in large quantities to meet the demand of the papermaking industry, as well as a method for using these materials in papermaking, are also disclosed.

Abstract: A simple, efficient and inexpensive method of purifying magnesium sulfate from mixtures of epsomite and halite. The method allows for the preparation of substantially pure magnesium sulfate products. The method generally involves heating a mixture of epsomite and halite to form clusters of lower hydrated magnesium sulfate crystals and subsequently applying slight pressure to the clusters so that they collapse to yield fine, less hydrated magnesium sulfate crystals which can then be easily separated from the comparatively coarse halite crystals. The less hydrated magnesium sulfate crystals can be recrystallized to provide highly purified epsomite which can then be dehydrated to provide kieserite or anhydrous magnesium sulfate.

Abstract: A form of calcium carbonate having a blocky[-six-sided] rhombohedral crystal [habit ] structure and [a morphology, with] properties including a surface area of from about 3 to about 15 m.sup.2 /g, an average discrete particle size of from about 0.2 to about 0.9 micron, wherein the discrete particles have an aspect ratio less than 2, and a particle size distribution such that at least about 60 weight percent of the particles have a size within 50 percent of the equivalent discrete particle spherical diameter, suitable for use as a filler material in papermaking to improve the optical properties of the resulting paper, is disclosed.

Abstract: A process for recovery of metallic aluminum, sodium and potassium chloride and an aluminum oxide-metallic aluminum product from secondary aluminum dross. A secondary aluminum dross feed is separated by particle size into a first dross portion which is water leached, filtered, evaporated in an evaporator to produce crystallized sodium and potassium chloride salts, magnesium chloride remaining in solution. A purge stream is removed from the evaporator wherein the crystallized salts are separated therefrom. The purge stream is then discharged onto the crystallized salts.

Abstract: A process for the recovery of metallic aluminum, mixtures of salts, and an aluminum oxide-metallic aluminum product from secondary aluminum dross. The process includes treating the dross with leach water to dissolve the salt content. Magnesium chloride is preferably added to the leach water to maintain the pH in the range of about 7-8.5, thereby reducing ammonia production in the treating step and enhancing recovery of metallic aluminum.

Abstract: A process for the preparation in an aqueous medium of purified calcium sulfate, with high whiteness, characterized in that it comprises:a) the formation of an aqueous solution by dissolution of impure hemihydrated calcium sulfate, at a concentration at most of 13.0 grams per liter (expressed in dissolved CaSO.sub.4) and at a pH of at least 5.

Abstract: Disclosed is a process for preparing crystals of anhydrous sodium sulfide, the process being characterized in that the process comprises the steps of heating crystals of polyhydrate of sodium sulfide under a pressure of about 500 torr or less at a temperature varying not more than .+-.about 10.degree. C. from the phase transition point between polyhydrate crystals and monohydrate crystals of sodium sulfide for about 2 hours or longer and further heating the monohydrate under atmospheric or reduced pressure at about 90.degree. to about 200.degree. C. for about 2 hours or longer.