Abstract: A process is provided for increasing the rate of solar evaporation of water from alkaline trona-process waste liquors which comprises introducing to the waste liquors an effective amount of a dye selected from the group consisting of Acid Black 2 and Acid Green 1, and subjecting said waste liquors to solar radiation for evaporation of water therefrom.

Abstract: In crystallization of a carbonate of sodium from aqueous solutions, a water soluble homopolymer of oxyethylene or block copolymer of oxyethylene and oxypropylene is employed as a defoamer. The presence of the defoamer in the resulting sodium carbonate does not adversely interfere with carbon dioxide absorption in subsequent production of sodium bicarbonate.

Abstract: A process is provided for the recovery of chemicals, such as chlorides, sulfates, carbonates and borates of such alkali metals as sodium and potassium, among others, from underground brines associated with an ore body containing said chemicals, wherein the underground brine is pumped to the surface and confined over said ore body where it is concentrated by solar evaporation and the concentrated brine returned to an underground basin adjacent said ore body and stored for later removal by pumping for the subsequent recovery of chemicals therefrom. Thus, solar evaporation is used to produce the desired concentration of brine to optimize the subsequent recovery of chemicals therefrom, thereby resulting in substantial savings in overall energy costs.

Abstract: A method of obtaining caustic soda and pure sodium chloride from an electrolytic cell liquor containing also sulfate ions including the steps of concentrating the liquor through multiple effect evaporation, cooling the concentrate obtained, separating the sodium chloride and the salt containing sulfate and recovering the caustic soda, whereby during a first stage the liquor is evaporated so as to precipitate only sodium chloride which is removed, in a second stage a solid phase is formed of sodium chloride, sodium sulfate and triple salt of caustic soda, sodium chloride and sodium sulfate, with said solid phase being contacted with a caustic soda solution of less than about 35% by weight concentration, so as to decompose said triple salt, removing the salt containing sulfate, and in a third stage the solution from the second stage is cooled to precipitate said triple salt of caustic soda, sodium chloride and sodium sulfate, which is separated from the caustic soda which does not crystallize and is removed fro

Abstract: Tributoxyethylphosphate is useful in controlling foam produced during the evaporative crystallization of calcined trona solutions. The chemical is effective at low concentrations, i.e. 1 to 30 ppm, and does not significantly alter the crystal habit of the sodium carbonate crystals.

Abstract: A subterranean salt deposit is solution mined, and the resulting calcium- and sulfate-contaminated brine is treated, e.g., by soda ash, to precipitate insoluble calcium compounds. The resulting slurry is settled, and the effluent clear brine is evaporated in a series of solar ponds to produce high-grade sodium chloride.The brine becomes progressively more concentrated with respect to sodium sulfate as it moves through the solar ponds. The sulfate-enriched brine may be recycled to the solution mine, evaporated to form a sulfate-contaminated sodium chloride crystal crop, or it may be subjected to winter cooling to remove sulfate values as Glauber's salt, the residual brine being recycled to the solar ponds or the solution mine.

Abstract: An aqueous solution of sodium hydroxide containing soluble impurities such as a concentrated catholyte produced by a diaphragm electrolysis is cooled by a coolant or a heat-exchanger to form a slurry containing sodium hydroxide hydrate crystals and fine impurity crystals. The fine impurity crystals are adsorbed on bubbles which are formed by vaporizing a dissolved coolant or introducing a gas in the slurry and separated from the slurry.

Abstract: Soda values from the crystallizer mother liquor purge in the process of making sodium carbonate from trona are recovered by (1) mixing the purge with treating agent of magnesium oxide, aluminum oxide, bauxite, certain fine particle size calcined trona, insoluble impurities obtained in the trona-soda ash process, or mixtures thereof, (2) evaporating the resulting mixture to dryness and calcining it to insolubilize soluble silicates and to reduce contamination with carbonaceous impurities, and (3) leaching the calcined mixture with water or aqueous sodium carbonate solution.

Abstract: In the production of anhydrous sodium dithionite by reacting sodium formate, an alkaline sodium compound and sulfurous acid anhydride in hydrous methanol, a process for treating the mother liquor, which comprises cooling the mother liquor left after the separation of the resulting anhydrous sodium dithionite to a temperature in the range of +5.degree. to -30.degree. C, and separating the precipitated sodium thiosulfate by filtration.

Abstract: Borax 10 mol or a mixture of ground borate ore, and borax 10 mol, can be effectively dehydrated to produce a product having approximately 62% B.sub.2 O.sub.3 and up to about three to four percent insolubles in a three-stage fluid bed dehydration process followed by compaction of the dehydrated borax.

Abstract: Soda values from the crystallizer purge liquor from the process of making sodium carbonate from trona are recovered by cooling the purge liquor to temperature below about 32.degree. C. to effect crystallization of sodium carbonate decahydrate crystals therefrom, and recovering the decahydrate crystals. Optionally, the decahydrate crystals may be heated to convert them to sodium carbonate monohydrate crystals. Sensible heat of the crystallizer purge liquor and/or sensible heat and latent heat of vaporization of the sodium carbonate process crystallizer vapors may be recovered by using it to heat the sodium carbonate decahydrate crystals to convert them to sodium carbonate monohydrate crystals.

Abstract: In the process for making sodium carbonate from trona, the soluble silicate content of crystallizer mother liquor from which sodium carbonate precursor crystals are obtained by evaporative crystallization is reduced by digesting the mother liquor at elevated temperature in the presence of certain activated insolubles, followed by separating the insolubles from the digested mother liquor. These activated insolubles are obtained by calcining crushed trona, dissolving the calcined trona in an aqueous medium to obtain a solution of sodium carbonate containing insolubles, separating the insolubles and activating them by calcination at elevated temperature.

Abstract: In the process of making sodium carbonate from trona involving the steps of crushing the trona, calcining the crushed trona, dissolving the calcined trona to obtain a solution comprising sodium carbonate and insoluble impurities contaminated by soluble silicates and soluble carbonaceous matter, contamination of the sodium carbonate solution with soluble carbonaceous matter is reduced by the improvement which comprises calcining the crushed trona at temperature of 300.degree. C. to 600.degree. C. in the presence of magnesium oxide. When the trona is calcined in the presence of magnesium oxide at temperature of 350.degree. to 600.degree. C., then the sodium carbonate solution is low in both soluble carbonaceous matter as well as insoluble silicates.

Abstract: In the process for making sodium carbonate from trona, the soluble silicate content of crystallizer mother liquor from which sodium carbonate precursor crystals are obtained by evaporative crystallization is reduced by the method which comprises:1. digesting said mother liquor at elevated temperature for time sufficient to reduce soluble silicates, in the presence as treating agent of insolubles which have been obtained by (a) calcination of crushed trona, (b) segregation of a fine particle size fraction from the calcined trona, (c) dissolution of said fine particle size fraction in an aqueous medium to obtain a solution comprising sodium carbonate and insolubles, followed by (d) separating insolubles, and2. separating the insolubles from the digested mother liquor, and recycling the mother liquor to the process.

Abstract: In the process of making sodium carbonate from trona by the method involving crushing the trona, calcining it and dissolving it in an aqueous medium for purification by crystallization, soluble silicate contamination of the crystallization liquor is reduced by an improvement which involves: (a) segregating the calcined trona into a coarse and a fine fraction; (b) separately dissolving the coarse and fine fractions to obtain aqueous solutions of sodium carbonate, sodium silicates and insoluble impurities; (c) optionally adding to the solution of the fine fraction insoluble impurities which have been separated from a solution of such fine fraction in a previous operation; followed by (d) digesting the solution of the fine fraction containing added insolubles at elevated temperature to insolubilize soluble silicates and separating the digested solution from insoluble impurities.

Abstract: Method of preparing refined, dense soda ash from crude trona by calcining the crude trona to crude sodium carbonate, mixing the crude sodium carbonate with an aqueous solution of soda ash or water to form a substantially saturated crude sodium carbonate solution containing coarse and fine insolubles, clarifying the crude sodium carbonate solution, passing the clarified sodium carbonate solution upwardly through an expanded carbon bed to remove organic impurities, evaporating the carbon-treated sodium carbonate solution to crystallize sodium carbonate monohydrate crystals, separating the sodium carbonate monohydrate crystals and calcining them to dense soda ash.

Abstract: Process for producing high bulk density sodium carbonate monohydrate crystals from sodium carbonate solutions wherein the sodium carbonate monohydrate is crystallized in the presence of at least 30 parts per million soluble aluminum ions.

Abstract: Anhydrous sodium sulfite is made by a process involving introducing substantially anhydrous sodium carbonate concurrently with sulfur dioxide-containing gas into a saturated solution of sodium sulfite maintained at pH of between about 6.5 and about 7.6 at temperature above about 35.degree. C. to form a slurry of anhydrous sodium sulfite crystals, and withdrawing the crystals from the slurry. The process is initiated using a concentrated sodium sulfite solution containing less than about 3 ppm of dissolved iron.

Abstract: Abrasion resistant sodium perborate monohydrate is prepared by treating sodium perborate monohydrate with at least 5% of water at a temperature of 20.degree. - 90.degree. C. in a moistening unit and then drying at a temperature beginning at 40.degree. C. and increasing to a maximum of 90.degree. C.

Abstract: Abrasion resistant and coarser sodium perborate tetrahydrate is prepared by reacting an aqueous sodium metaborate solution with aqueous hydrogen peroxide while avoiding free active oxygen and free alkali in the reaction medium. A strongly supersaturated perborate tetrahydrate solution having 200 to 700 grams/liter of perborate tetrahydrate is introduced into a previously prepared suspension of mother liquor and innoculant crystals which contains 100 to 500 grams/liter of suspension of seed crystals at such a rate that not more than 30 grams of perborate tetrahydrate grow as crystals per minute per square meter apparent innoculant surface area at 20 to 40.degree. C. and a rate of crystallization growth of not more than 100% whereupon the temperature is reduced to 15.degree. C. within 15 to 30 minutes, in a given case in a subsequent step. In another aspect of the invention the perborate is added at a point not earlier than the crystallizer.

Abstract: Method for clarifying a carbonate process solution containing suspended insolubles which solution is used in the preparation of crystals selected from the group consisting of sodium bicarbonate, sodium sesquicarbonate, anhydrous sodium carbonate, and sodium carbonate monohydrate, which comprises dispersing in the carbonate process solution prior to crystallization a cationic flocculating agent comprising a substituted guar gum containing one quaternary ammonium group per 2 to 12 monosaccharide units to agglomerate the suspended insolubles so the suspended insolubles will readily settle out of the carbonate process solution.This invention relates to a process for clarifying a carbonate process solution used in the preparation of sodium bicarbonate, sodium sesquicarbonate, anhydrous sodium carbonate or sodium carbonate monohydrate crystals.

Abstract: Salable salt values in a complex brine are recovered by cooling to crystallize mirabilite, then using solar evaporations to recover readily processable groupings of sodium salts and potassium salts.

Abstract: Process for producing sodium carbonate monohydrate crystals having a high bulk density, blocky crystal shape, and uniform particle size distribution from sodium carbonate solutions wherein the sodium carbonate monohydrate is crystallized in the presence of magnesium ions and sodium dodecylbenzenesulfonate.

Abstract: A process is provided for the recovery of chemicals, such as chlorides, sulfates, carbonates and borates of such alkali metals as sodium and potassium, among others, from underground brines associated with an ore body containing said chemicals, wherein the underground brine is pumped to the surface and confined over said ore body where it is concentrated by solar evaporation and the concentrated brine returned to an underground basin adjacent said ore body and stored for later removal by pumping for the subsequent recovery of chemicals therefrom. Thus, solar evaporation is used to produce the desired concentration of brine to optimize the subsequent recovery of chemicals therefrom, thereby resulting in substantial savings in overall energy costs.

Abstract: Nahcolite-bearing oil shale ore is heated to produce a distinct color change in the nahcolite, differentiating the nahcolite from the host oil shale for optical sorting, and such sorting is then accomplished by optical sorting means.

Abstract: Sodium carbonate monohydrate from crude trona is prepared by calcining the crude trona to crude sodium carbonate, dissolving the crude sodium carbonate in an aqueous solution, clarifying and filtering the resulting solution to remove insoluble material to form a carbonate process solution, subjecting the carbonate process solution to a first crystallization to form a first crop of sodium carbonate monohydrate crystals from said carbonate process solution, subjecting the mother liquor separated from the first crop of monohydrate crystals and having a higher concentration of soluble organics to a second crystallization, including a crystallization temperature higher than that employed to obtain the first crop of said monohydrate crystals, to effect formation of a second crop of sodium carbonate monohydrate crystals, and separating said second crop of monohydrate crystals from a mother liquor having an organics level higher than said carbonate process solution and said mother liquor separated from said first cry

Abstract: A process is provided for the continuous separation of suspended basic alkali metal azide particles from a liquid reaction medium by bringing the liquid reaction medium into contact with a non-reactive mineral oil whereby the suspended metal azide particles migrate into the mineral oil phase and are thereafter separated therefrom.

Abstract: Smelts produced in Kraft mill and soda mill spent pulping liquor recovery operations and containing sodium chloride are treated to remove sodium chloride therefrom in pure form while the removal of usable components is avoided. A solid mixture of sodium chloride, sodium carbonate and sodium sulphate is provided in the case of the soda mill, or first is separated from the sodium sulphide in the case of the Kraft mill. Thereafter, the solid mixture is leached to remove the sodium carbonate and sodium sulphate while leaving the sodium chloride in a substantially pure form, the resulting leach liquor being refrigerated to deposit sodium carbonate and sodium sulphate. The mother liquor, after removal of the deposited salts is recycled to the solid mixture leaching step.