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: A compound of a chemical element to be isotopically enriched is placed in a working zone with an auxiliary material and temperature and pressure conditions are controlled to cause a liquid solution to occur. The liquid solution is injected through a nozzle into a separating chamber, for example, at substantially constant pressure and with slight elevation of temperature, to cause a phase change, the liquid solution yielding a solid phase which is enriched in respect of an isotope of the chemical element and a gaseous phase which is depleted. The series of such stages are arranged in cascade with the enriched solid phase being passed forward to the following stage for further enrichment and the depleted gaseous phase being passed back to the previous stage for further depletion. The arrangement is especially applicable to uranium enrichment, wherein the compound is uranium hexafluoride and the auxiliary material is tungsten hexafluoride.

Abstract: Metal salts which are crystallizable from a saturated aqueous solution of the salt in the presence of a dispersion of polytetrafluoroethylene (hereinafter referred to as PTFE) resin are grown as geometrically better defined and larger crystals than those grown from an unseeded saturated solution.

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: A gelling agent is added to a brine containing magnesium chloride to convert the brine into a gel which is spray dried to produce dried magnesium chloride comprising substantially solid discrete particles of magnesium chloride having bulk densities in the range from about 12 to 45 pounds per cubic foot.

Abstract: Evaporite minerals comprising mixtures of relatively coarse salts are treated in a manner such that certain of said salts are converted by recrystallization to very finely divided form and then separated from the coarse salts by size classification such as elutriation, the treatment being especially useful in a process for the recovery of potassium sulfate from marine evaporite mixtures such as kainite and halite.

Abstract: A malleable or press-forgeable ingot of barium fluoride, for use as an optical body, may be grown from an ultra-pure precipitate of barium fluoride which contains less than 10 parts per million (ppm) of strontium or calcium. A process is disclosed for crystallizing barium nitrate crystals in the presence of nitric acid, reacting barium nitrate with ammonium carbonate to form barium carbonate, recovering barium carbonate crystals, suspending the barium carbonate crystals in water and precipitating barium fluoride with hydrofluoric acid. The barium fluoride crystals are recovered, dried and then calcined in the presence of ammonium fluoride or bifluoride. Barium fluoride (BaF.sub.2) crystals obtained by the process of this invention contain less than 10 ppm of each strontium and calcium.Crystals of an alkaline earth metal fluoride which have been calcined in the presence of a fluoride of ammonium are unexpectedly densified, and are particularly suited for melt-growth of an ingot in a known manner.

Abstract: Single crystals of Hg.sub.3 TeO.sub.6, which are useful in, for example, acousto-optic applications, are grown on rotating seed crystals in aqueous solution at an elevated temperature. A two-step process is employed in which supersaturation is achieved by a substantially homogeneous increase in pH throughout the solution under substantially isothermal conditions, followed by a decrease in temperature at substantially constant pH. The homogeneous increase in pH is attained by adding a compound such as urea whose rate of hydrolysis may be controlled by solution pH and temperature. The use of such a compound ensures thorough mixing of the compound in the solution before the compound hydrolyzes to produce a pH-altering substance.

Abstract: A process for producing amethyst crystals which involves growing colourless quartz crystals by a hydrothermal method of a temperature drop in a high-pressure autoclave on crystalline quartz seed plates oriented parallel to pinacoid crystallographic planes {0001} or to planes inclined to said pinacoid planes at an angle of up to 15.degree. with the use of silica as a charge, said growing being effected from aqueous solutions of ammonium fluoride with a concentration of from 5 to 30% by weight and containing iron introduced into the autoclave in the form of its oxydic or hydroxydic compounds in an amount ranging from 5 to 30 g/l of the solution. Said growing of colourless quartz crystals is effected at a crystallization temperature within the range of from 150.degree. to 500.degree.C under a pressure of from 10 to 1,200 kg/cm.sup.2 and at a crystal growth rate of from 0.05 to 1.5 mm/day.

Abstract: A method for growing single crystals which utilizes calcium nitride as a solvent system in the molten solution growth of bulk aluminum nitride crystals.