Abstract: The negative effects of sodium oxylate on the crystallization of aluminum trihydrate from Bayer process liquors may be eliminated or curtailed by adding an effective amount of a polyacrylic acid with a molecular weight about 1,000,000 and containing at least 50 mole percent acrylic acid monomer to pregnant Bayer process liquors.

Abstract: Lithium is continuously converted into lithium hydride, is suitable phase contactor/decanter apparatus, by continuously hydrogenating in a first reaction zone, at elevated temperatures, an agitated intimate admixture of metallic lithium in a mixture of molten salts, continuously discharging the effluent of said hydrogenation reaction to a second zone of decantation, whereby said effluent is separated into a floating light phase essentially consisting of unreacted lithium metal and a heavy phase which comprises product lithium hydride dissolved in said mixture of molten salts, continuously recycling floating light phase back to the hydrogenation reaction zone, continuously withdrawing heavy phase from said zone of decantation, and recovering product lithium hydride from said withdrawn heavy phase.

Abstract: Heavy residues produced by noble metal catalyzed carbonylation reactions and containing Group VIII noble metals, particularly rhodium, are treated with a mixture of immiscible liquids to precipitate solids containing substantially all of the noble metal contained in the residues. The solids may be returned directly for reuse in the carbonylation reaction. One group of liquids consists of water with immiscible alcohols or hydrocarbons, or mixtures thereof. A second group consists of acetic anhydride with immiscible hydrocarbons.

Abstract: A process is disclosed for producing pure molybdenum which involves contacting a molybdate solution with a true liquid alkaloid in an amount sufficient to form an alkaloid-molybdenum compound with essentially all of the molybdenum. The resulting alkaloid-treated solution is adjusted to a pH of from about 2 to 4 to form a precipitate consisting essentially of the compound and a mother liquor. The precipitate is then separated from the mother liquor and dissolved in ammonium hydroxide to form a two phase system consisting essentially of an alkaloid phase and a molybdenum phase followed by separation of the two phases. A pure ammonium molybdate compound is then crystallized from the molybdenum phase.

Abstract: Processes are described for preparing pure ammonium molybdate from impure roasted molybdenum concentrates. An aqueous solution of nitric acid and ammonium nitrate is contacted with impure molybdenum concentrate to solubilize a major portion of the impurities. The resulting molybdenum concentrate is digested in ammonium hydroxide under conditions that maximize iron precipitation and removal. The resulting ammonium molybdate solution is separated from the sludge and further purified by chelating cation exchange resin in the ammonium form.

Abstract: Processes are described for preparing pure ammonium molybdate from impure roasted molybdenum concentrates. An aqueous solution of nitric acid, ammonium sulfate, and ammonium nitrate is contacted with impure molybdenum concentrate to solubilize a major portion of the impurities. The resulting molybdenum concentrate is digested in ammonium hydroxide under conditions that maximize iron precipitation and removal. The resulting ammonium molybdate solution is separated from the sludge and further purified by chelating cation exchange resin in the ammonium form.

Abstract: A process is disclosed for recovering tungsten and rhenium from a tungsten and rhenium source. The process involves firing the source in an oxidizing atmosphere at a sufficient temperature for a sufficient time to convert the tungsten and rhenium to their respective oxides, to remove a portion of the rhenium as volatilized oxide, and to form a first fired material containing essentially all of the tungsten and the remaining portion of the rhenium, increasing the surface area of the resulting oxidized tungsten, and firing the first fired material in an oxidizing atmosphere at a sufficient temperature for a sufficient time to remove essentially all of the remaining portion of the rhenium as volatilized oxidized rhenium and to form an essentially rhenium-free oxidized tungsten.

Abstract: A process for converting tungsten bearing material to sodium tungstate by adding an oxidizing reactant in small increments to a heated mixture of fused sodium hydroxide and the tungsten bearing material while the temperature is maintained at from about 500.degree. C. to about 700.degree. C.

Abstract: Processes are described for preparing pure ammonium molybdate from impure roasted molybdenum concentrates. An aqueous solution of hydrochloric acid and ammonium nitrate is contacted with impure molybdenum concentrate to solubilize a major portion of the impurities. The resulting molybdenum concentrate is digested in ammonium hydroxide under conditions that maximize iron precipitation and removal. The resulting ammonium molybdate solution is separated from the sludge and further purified by chelating cation exchange resin in the ammonium form.

Abstract: Manganese(II)salt solutions containing ammonium salt are made by subjecting a manganese-containing compound to processing treatment with an ammonium salt solution. A boiling temperature of 57.degree.-68.degree. C. is established in the suspension to be subjected to the processing treatment, by application of a vacuum. The ammonium salt solution used contains 0.5-2.5 mol/l diammonium sulfate or 1.0-5.0 mol/l ammonium nitrate.

Abstract: A process is disclosed for separating tungsten from a solution containing tungstate and perrhenate ions. The process involves reacting a sufficient amount of hydrochloric acid with the solution at a sufficient temperature to form a solid containing essentially all of the tungsten and a liquor containing essentially all of the rhenium, and separating the solid from the liquor.

Abstract: The present invention relates to the selective extraction of rhenium metal from aqueous sulfuric acid solutions. More particularly, it relates to the selective extraction of rhenium metal from sulfuric acid leach solutions, resulting from the leaching of spent petroleum reforming catalysts, by the use of tertiary phosphine oxide extraction compounds.

Abstract: A process is disclosed for recovering tungsten and rhenium from a relatively impure tungsten and rhenium solution. The process involves adjusting the pH of the solution to from about 9.0 to about 10.0 to precipitate impurities, and removing the impurities. The purified solution is adjusted to a pH of from about 0.5 to about 7.0 with a mineral acid. To the purified solution is added a solution containing sufficient hexamine to subsequently form a first hexamine tungsten solid containing the major portion of the tungsten. The hexamine solution is at essentially at the same pH as that of the pH adjusted purified solution. The resulting hexamine-tungsten-rhenium mixture is agitated at a sufficiently low temperature for a sufficient time to form the first solid and a first mother liquor containing the major portion of the rhenium. The first solid is separated from the first mother liquor.

Abstract: A process is disclosed for recovering molybdenum from molybdenum disulfide. The process involves forming a slurry of the molybdenum disulfide in a solution of an alkali metal hydroxide, the amount of hydroxide being sufficient to react with at least a portion of the molybdenum disulfide to form an alkali metal molybdate and an alkali sulfate, heating the slurry in an oxidizing atmosphere at an elevated temperature and pressure and for a sufficient time to effect the conversion to the molybdate, and separating the pregnant liquor containing the molybdate from any residue. To the pregnant liquor is then added a sufficient amount of a hexamine to form a hexamine-molybdenum compound containing the major portion of the molybdenum, followed by adjusting the pH to from about 1.5 to about 3.8 to precipitate the major portion of the hexamine-molybdenum compound, and separating the compound from the resulting mother liquor.

Abstract: A process for purifying at least a fraction of a solution in the Bayer cycle, which is preferably taken off after decomposition of the sodium aluminate, before or after concentration thereof, by causing the precipitation of the sodium oxalate in solution by the introduction of an agent for destabilization of the state of supersaturation of the sodium oxalate, which is characterized in that the supersaturation destabilization agent introduced into the Bayer solution to cause precipitation of the sodium oxalate is selected from the group comprising calcium oxalate and barium oxalate and that, in the case of solutions charged with degraded organic materials which generally result from high-temperature attack on bauxites with high proportions of humic materials, an anionic synthetic polyelectrolyte of high molecular mass is previously introduced into said solutions in order to increase the efficiency of the purification effect.

Abstract: Substantially pure boehmite is produced by heating an aqueous sodium aluminate solution to a temperature of about 115.degree.-145.degree. C., preferably about 120.degree.-130.degree. C., treating the heated solution with alumina seed material and separating a boehmite precipitate from the solution. A particularly preferred seed material is boehmite gel.

Abstract: A method for producing tetrachloride of a metal selected from the group consisting of titanium and zirconium comprising: providing a reaction chamber which is defined by a wall structure of refractory material and arranged in an airtight encasement of metal, said reaction chamber comprising a reaction zone ranging downwards from an intermediate level thereof, said encasement including a jacket formed of a double wall construction around the reaction zone, communicating means between the inside of said jacket and said reaction chamber, heating said reaction chamber, filling said jacket with a gas, introducing a solid reaction mixture comprising a compound of the metal to be chlorinated, supplying a gas mixture comprising chlorine to said reaction zone through a tube connected to the chamber bottom to cause reaction at a positive pressure over the atmosphere to produce the tetrachloride of the metal, maintaining a positive pressure relative to the atmosphere in both said jacket and said reaction chamber and a p

Abstract: A process is disclosed for preparing impermeable, polycrystalline samples of Pb-.beta."-alumina ceramic from Na-.beta."-alumina ceramic by ion exchange. The process comprises two steps. The first step is a high-temperature vapor phase exchange of Na by K, followed by substitution of Pb for K by immersing the sample in a molten Pb salt bath. The result is a polycrystalline Pb-.beta."-alumina ceramic that is substantially crack-free.

Abstract: High surface area, wide-pore-containing porous aluminas are prepared by mulling together aluminum nitrate derived hydrogels with sodium aluminate derived hydrogels, extruding, drying and calcining at 500.degree.-700.degree. C.

Abstract: Metals such as nickel and vanadium can be recovered from scrubber waste by first lowering the pH of the waste to a level at which its major metal constituents will be substantially solubilized, and then raising the pH in increments to successively precipitate the metals it contains.