Abstract: A process for alunite ore treatment which comprises roasting alunite in the presence of oxygen at a temperature of from 580.degree. to 620.degree. C. for 1 to 3 hours, decomposing the roasted alunite by exposure to reducing agents at a temperature of from 580.degree. to 620.degree. C., subjecting the reduced alunite to hydrochemical treatment by use of a sodium hydroxide solution of concentration from 100 to 150 g/lit in terms of Na.sub.2 O, decomposing the resultant aluminate liquor, with the aluminum hydroxide component precipitating out, and finally, washing and baking the aluminum hydroxide precipitate to obtain same as an end product. The invention provides a comprehensive method of treatment of alunite ores the associated rock whereof comprises silica in the form of opal and chalcedony earlier believed to be refractory to comprehensive treatment by alkaline methods.

Abstract: A process for recovering antimony and sodium compounds from antimony-containing spent ethylene glycol residues resulting from the manufacture of polyethylene-terephthalate polyester, which comprises combusting the spent glycol residues to produce an ash, and then contacting the ash with water to form an ash-water mixture having a liquid phase and a solid phase, the water-soluble sodium compounds being essentially contained in the liquid phase and the water-insoluble antimony compounds being essentially contained in the solid phase. The liquid phase and solid phase are then separated in order to recover therefrom sodium and antimony compounds, respectively.

Abstract: Potassium is recovered as a dilute KOH solution from residue solids resulting from conversion of manganese ore to K.sub.2 MnO.sub.4 by reacting the solids with a Ca(OH).sub.2 under specified conditions. The resulting KOH solution can be returned to the K.sub.2 MnO.sub.4 plant and the solids of reduced potassium content are suitable for disposal in a landfill.

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: Carnallite, comprising principally of MgCl.sub.2. KCl.6H.sub.2 O, with varying amounts of sodium chloride and other impurities, is dissolved in a lower saturated monohydric aliphatic alcohol having from one to four carbon atoms such as methanol, ethanol, propanol, isopropyl alcohol, N-butyl alcohol, secondary-butyl alcohol, iso-butyl alcohol, and tert-butyl alcohol, to dissolve the magnesium chloride therein leaving an insoluble residue of principally potassium chloride, sodium chloride and other materials. The residue is filtered from the solution, dried and stored or further processed. The filtrate, a magnesium chloride hydrate solution is further processed by injecting steam or water into the solution and removing, e.g., evaporating the methanol from the solution leaving an aqueous magnesium chloride hexahydrate brine. The recovered methanol is dried by distillation, condensed and recycled.

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 recovery of molybdenum and rhenium values from sulfide ores, silica impurity is reduced to low levels by adding alumina to a carbonate fusion mix in an amount sufficient to combine with the silica present to form insoluble aluminum silicates, thus preventing its removal from the fusion mass during removal of soluble molybdenum and rhenium values by leaching, and thereby avoiding the necessity for conventional subsequent precipitation and filtration removal steps.

Abstract: The present invention relates to an improved method of solution mining potassium chloride from subterranean ore deposits containing both potassium chloride and sodium chloride. By the present invention, an aqueous medium is passed through the ore deposits so that potassium chloride and sodium chloride are dissolved therein. Magnesium chloride is combined with the aqueous brine solution formed so that an aqueous brine solution containing potassium chloride, sodium chloride and magnesium chloride in specific proportions is produced, and the solubility of potassium chloride in the solution is reduced. The combined aqueous brine solution is then concentrated so that it is substantially saturated with potassium chloride, and the concentrated solution is cooled to cause the precipitation of substantially pure potassium chloride.

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: A new self-cleaning salt dissolver construction which includes a special dissolving zone which supports the salt for dissolution while at the same time permitting the collection of sludge-impurities in the dissolving zone such that the sludge-impurities can be removed by a special cleaning operation when desired, without requiring the removal of the salt bed from the dissolver.