Abstract: A method for preparing nickel/manganese/lithium/cobalt sulfate and tricobalt tetraoxide from battery wastes adopts the following process: dissolving battery wastes with acid, removing iron and aluminum, removing calcium, magnesium and copper, carrying extraction separation, and carrying out evaporative crystallization to prepare nickel sulfate, manganese sulfate, lithium sulfate, cobalt sulfate or/and tricobalt tetraoxide. By using the method, multiple metal elements, such as nickel, manganese, lithium and cobalt, can be simultaneously recovered from the battery wastes, the recovered products are high in purity and can reach battery grade, battery-grade tricobalt tetraoxide can also be directly produced. The method is simple in process, low in energy consumption and free in exhaust gas pollution, and can realize zero release of wastewater.

Abstract: Provided is a method for purifying a difluorophosphate, in which a difluorophosphate is purified to a high purity. The method includes a method for purifying a difluorophosphate, comprising bringing hydrogen fluoride into contact with a difluorophosphate containing an impurity and subsequently heating and drying the difluorophosphate, or bringing the hydrogen fluoride into contact with the difluorophosphate containing the impurity while heating and drying the difluorophosphate containing the impurity, thereby removing the impurity.

Abstract: The invention generally relates to methods of removing potassium, rubidium, and/or cesium, selectively or in combination, from brines using tetrafluoroborates. Also disclosed are methods of producing potassium, rubidium, and/or cesium chlorides using ionic liquids and exchange media. This invention also generally relates to treated geothermal brine compositions containing reduced concentrations of silica, iron, and potassium compared to the untreated brines. Exemplary compositions of the treated brine contain a concentration of silica ranging from about 0 mg/kg to about 15 mg/kg, a concentration of iron ranging from about 0 mg/kg to about 10 mg/kg, and a concentration of potassium ranging from about 300 mg/kg to about 8500 mg/kg. Other exemplary compositions of the treated brines also contain reduced concentrations of elements like rubidium, cesium, and lithium.

Abstract: This invention discloses improvements on previous inventions for catalytic conversion of coal and steam to methane. The disclosed improvements permit conversion of petroleum residua or heavy crude petroleum to methane and carbon dioxide such that nearly all of the heating value of the converted hydrocarbons is recovered as heating value of the product methane. The liquid feed is distributed over a fluidized solid particulate catalyst containing alkali metal and carbon as petroleum coke at elevated temperature and pressure from the lower stage and transported to the upper stage of a two-stage reactor. Particulate solids containing carbon and alkali metal are circulated between the two stages. Superheated steam and recycled hydrogen and carbon monoxide are fed to the lower stage, fluidizing the particulate solids and gasifying some of the carbon. The gas phase from the lower stage passes through the upper stage, completing the reaction of the gas phase.

Abstract: The present invention relates to a process for the production of intermediates useful in the processing of mineral sands and related materials characterized in that the process comprises:(a) dissolving a metal fluoride or metal chloride compound in an organic solvent; and either(b)(i) adding an ammonium fluoride to the metal fluoride or metal chloride compound dissolved in the organic solvent in step (a) to precipitate an ammonium fluorometallate from the organic solvent; and(ii) dissolving the ammonium fluorometallate from step (b)(i) in water and adding an alkali fluoride or an alkali chloride or an alkali nitrate to produce an alkali fluorometallate and an ammonium fluoride or an ammonium chloride or an ammonium nitrate; or(c) optionally adding the metal fluoride compound dissolved in the organic solvent in step (a) to an alkali fluoride dissolved in water or in aqueous hydrogen fluoride to produce an alkali fluorometallate directly.

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: Recovery of cerium values from fluoride-containing ores such as bastnasite is enhanced. The ore is ground, roasted, and leached with dilute hydrochloric acid to produce an ore concentrate. The concentrate is treated with a solution of hydrochloric acid and boric acid to solubilize cerium values and convert fluoride to tetrafluoroborate ion. Tetrafluoroborate is removed from the solution, e.g., by precipitation, and the solution is further processed for recovery of cerium values. Removal of tetrafluoroborate avoids loss of cerium as insoluble cerium tetrafluorborate during said further processing.

Abstract: A process for the treatment of spent pot linings impregnated with alkali metal cyanide and fluoric products by grinding previously crushed pot linings in the presence of lime, suspending the ground pot linings in an aqueous medium in order to precipitate a flux in the form of CaF.sub.2 accompanied by the release of soda, followed by the heating of the suspension at a temperature T>140.degree. C. in the presence of clay to form, after fixing the free soda, insoluble synthetic silicate compounds of the feldspathoid or zeolite type and finally the separation by filtration of the resulting solid phase from the liquid phase, which liquid phase is recycled to form a new ground pot lining suspension.

Abstract: Recovery of cerium values from fluoride-containing ores such as bastnasite is enhanced. The ore is ground, roasted, and leached with dilute hydrochloric acid to produce an ore concentrate. The concentrate is treated with a solution of hydrochloric acid and boric acid to solubilize cerium values and convert fluoride to tetrafluoroborate ion. Tetrafluoroborate is removed from the solution, e.g., by precipitation, and the solution is further processed for recovery of cerium values. Removal of tetrafluoroborate avoids loss of cerium as insoluble cerium tetrafluorborate during said further processing.

Abstract: Fluoride-containing wastes, arising in the aluminium industry, particularly spent cell linings from reduction cells, are digested with caustic soda for conversion of sodium cryolite to NaF.By use of very strong caustic soda NaF may be left in the solid residues after removal of the residual liquor and recovered from such residues by water leaching.As an alternative weaker caustic soda may be used in the digestion stage and subsequently be crystallised out from the residual liquor, after separation from the solid residues, by evaporating and/or cooling the liquor. The precipitated NaF is then conventiently redissolved in water.The NaF solution prepared by either route is then preferably subjected to electrodialysis to recover a solution of HF from it. Such HF is conveniently converted to AlF.sub.3 by reaction with alumina.

Abstract: A process for the stripping of cesium ions from an aqueous solution in which a precipitation agent is added to the aqueous solution and the resulting precipitate, containing the CS.sup.+ ions is stripped from the solution. Sodium or lithium tetraphenylborates, carrying electron-attracting substituents on the phenyl rings are employed as precipitation agent.

Abstract: A process is described for the recovery of silicon from a reaction mixture comprising silicon and an alkali metal fluoride.

Abstract: The disclosure relates to a process for making alkali metal phosphate solutions containing little fluorine from pre-purified alkali metal phosphate solutions obtained from crude phosphoric acid by extracting the acid with an organic solvent being immiscible or only partially miscible with water, scrubbing the crude extract with water or an alkali metal solution, re-extracting the phosphoric acid from the scrubbed extract with the use of an aqueous alkali metal solution while establishing an alkali metal/P-molar ratio equal to or larger than 1:1, and separating the resulting organic phase from the pre-purified alkali metal phosphate solution obtained.To this end, the disclosure provides:(a) for the pre-purified alkali metal phosphate solution to be stirred at 60.degree.-120.degree. C. into a compound of an alkaline earth metal Me.sup.2+ with a solubility in water at 20.degree. C. of more than 0.01 mol Me.sup.

Abstract: The disclosure relates to a process for defluorinating alkali metal phosphate solutions. To this end, the disclosure provides for an alkali metal phosphate solution neutralized to a pH-value of more than 6 and pre-purified to be stirred at 60.degree. to 120.degree. C. into an alkaline earth metal compound. Alkaline earth metal compounds with a solubility in water of less than 5 g/l are used in the form of particles of which more than 50% have a size of less than 8 .mu.m. After a reaction period of 0.5 to 4 hours, the precipitate obtained is separated from the purified alkali metal phosphate solution.

Abstract: A process for the purification of spent liquor from an alumina precipitation stage is disclosed wherein the spent liquor is first contacted with 50 volume % or less ethanol to form a sodium oxalate precipitate and the, after removal of the sodium oxalate precipitate is contacted with over 50 volume % of ethanol extraction fluid to separate the mixture into a first layer comprising the ethanol and at least a portion of the caustic from the spent liquor and a second layer which comprises the remainder of the spent liquor. The spent liquor may then be subjected to a further precipitation to recover further alumina. The spent liquor remaining may be further treated in subsequent extraction steps to concentrate and dispose of undesirable impurities remaining.

Abstract: In accordance with the invention, spent liquor from an alumina precipitation stage is contacted with an extraction fluid to separate the mixture into a first layer comprising the extraction fluid and at least a portion of the caustic from the spent liquor and a second layer which comprises the remainder of the spent liquor. The spent liquor may then be subjected to a further precipitation to recover further alumina. The spent liquor remaining may be further treated in subsequent extraction steps to concentrate and dispose of undesirable impurities remaining.

Abstract: A method for recovery of fluoride values from spent potlining and fluoride containing insulating materials associated with the potlining is disclosed. Spent potlining and the insulating materials are reduced to a fine particle size and incinerated. The ash residue is leached with a dilute caustic and the leachate is treated with a calcium compound to precipitate calcium fluoride. The calcium fluoride is dried to a moisture content of less than 0.1 percent and is treated with about 93 to 99 percent concentration of sulfuric acid to produce hydrogen fluoride gas and a metal sulfate. The hydrogen fluoride gas is fed into an alumina dry scrubber to produce alumina with absorbed fluorides to be used as feed material to reduction cells used in the manufacture of aluminum by electrolytic reduction. The metal sulfate residue is treated with lime and constitutes an environmentally safe product which can be disposed of as landfill material.

Abstract: An alkali monofluorophosphate expressed by the formula M.sub.2 PO.sub.3 F, where M represents Na or K, can readily be synthesized under a relatively mild reaction condition by making HF gas contact with powdery or fine granular M.sub.4 P.sub.2 O.sub.7 or M.sub.2 HPO.sub.4 placed in a reaction vessel and maintained at a temperature in the range from about 200.degree. C. to about 450.degree. C., and more preferably in the range of 280.degree.-360.degree. C. It is suitable to make HF gas continuously flow into and pass through the reaction vessel until the total quantity of HF flowed into the vessel amounts to 100 to 150% of the theoretical value for conversion of M.sub.4 P.sub.2 O.sub.7 or M.sub.2 HPO.sub.4 to M.sub.2 PO.sub.3 F.

Abstract: Disclosed is a process for producing sodium tripolyphosphate (STPP) with reduced amounts of silicon and magnesium impurities from wet process phosphoric acid.

Abstract: A process for recovering fluorine and silicon values from a waste-water stream produced in a wet-process phosphoric acid process which comprises:(a) diluting concentrated sulfuric acid with the waste-water stream and producing an SiF.sub.4 -containing gas during the dilution;(b) scrubbing the SiF.sub.4 -containing gas with phosphoric acid to produce a phosphoric acid solution containing fluosilicic acid;(c) reacting sodium carbonate with the phosphoric acid solution to precipitate solid sodium silicofluoride; and(d) separating the solid sodium silicofluoride from the phosphoric acid.

Abstract: Potassium fluoride and silica are reacted with an aqueous solution of hydrofluorosilicic acid. The resulting potassium fluorosilicate is recovered. The potassium fluorosilicate may be further reacted with ammonia in water to form an aqueous mixture of ammonium fluoride and potassium fluoride. The ammonium fluoride is then heated in aqueous solution in the presence of excess potassium fluoride to release ammonia and to form potassium bifluoride. The potassium bifluoride is recovered from solution substantially free from ammonia and heated to release hydrogen fluoride. Alternatively, the recovered potassium bifluoride may be reacted with sodium fluoride to produce sodium bifluoride. The sodium bifluoride is then heated to release hydrogen fluoride.

Abstract: A process is disclosed for the production of lead carbonate by treatment of fluorine-containing mud produced in the polishing of lead glass with etching acid comprising:A. separating said mud from the etching acid;B. reacting the same with an aqueous alkali carbonate solution and filtering the solution;C. dissolving the residue in nitric acid and precipitating the fluorides in the form of alkali hexafluorosilicates by the addition of alkali ions at a pH of the solution under 4 and filtering out the precipitate; andD. adjusting the pH of the resulting solution to above 6.5 by the addition of alkali carbonate to the solution to precipitate basic lead carbonate.

Abstract: An alkali carbonate containing a fluorine compound is purified by dissolving the crude alkali carbonate in an aqueous solution or suspension of magnesium bicarbonate in order to transfer the fluorine impurity into the resulting colloidal flocculated precipitate whereby the fluorine is substantially separated from the aqueous solution of the alkali carbonate.