Abstract: A process is disclosed for producing tungstosilicic acid which involves adding sodium silicate to a first solution of sodium tungstate while assuring that the pH of the resulting mixture is from about 2 to about 6, the pH adjustments being made with a cation exchange resin on the hydrogen cycle, to produce a second solution. The solids are removed from the second solution which is digested at a temperature of greater than about 50.degree. C. and then contacted with a cation exchange resin on the hydrogen cycle to produce a third solution which is essentially a tungstosilicic acid solution containing at least about 99% by weight of the starting tungsten as tungstosilicic acid.

Abstract: A method for converting cobalt to cobalt powder is disclosed which comprises heating a starting mixture of cobalt and zinc in a non-reacting atomosphere at a first temperature of below the boiling point of zinc up to about 900.degree. C. in a non-reacting atmosphere for a length of time sufficient to cause the alloying of a portion of the zinc and cobalt, with the weight ratio of zinc to cobalt being less than about 10. The temperature of the resulting partially alloyed mixture is slowly raised to a second temperature of from about 900.degree. C. to about 960.degree. and is maintained for a time sufficient only to form a reaction product in which essentially all of the cobalt is alloyed with zinc and to keep the evaporation of zinc to a minimum. The reaction product is then heated at a pressure below atmospheric pressure at a third temperature of no greater than about 950.degree. C.

Abstract: An improvement is disclosed in a process wherein tungsten values are extracted from an aqueous alkali metal tungstate solution by an organic extractant, and then stripped from the organic with an ammonia solution, the improvement being removing bromine from the major portion of the stripped organic and thereafter using at least a portion of the resulting bromine-free stripped organic to make up at least a portion of the organic extractant.

Abstract: A process is disclosed for producing ammonium tetrathiomolybdate. The process involves reacting an ammoniacal molybdate solution with hydrogen sulfide gas, the solution and the gas being in a closed system and the flow of the gas being regulated at an elevated pressure to form a slurry consisting essentially of a solid essentially all of which is ammonium tetrathiomolybdate containing a portion of the starting molybdenum and a mother liquor containing the balance of the molybdenum. The slurry is then cooled to ambient temperature and the solid is removed from the major portion of the mother liquor. The solid is then washed with water and with alcohol followed by removal of the resulting respective water and alcohol washes to remove the remaining portion of the mother liquor and soluble impurities from the solid. The resulting washed solid is then dried at ambient temperature to form the final ammonium tetrathiomolybdate.

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: 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: 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 tungsten and rhenium from a tungsten and rhenium bearing solution. The process involves adding sufficient hydrochloric acid to the solution to form a first precipitate containing essentially all of the tungsten and a first mother liquor having an acid concentration of at least about 1.25 normal, and containing the major portion the rhenium, followed by separating the first precipitate from the first mother liquor. A source of sulfide ions is then added to the first mother liquor with agitation for a sufficient time and with the amount of sulfide ions being sufficient to form a second precipitate containing essentially all of the rhenium which was in the first mother liquor, and a second mother liquor, followed by separation of the second precipitate from the second mother liquor.

Abstract: In a process for recovering rhenium, a starting material containing tungsten and rhenium is reacted with sodium hydroxide and an oxidizing reactant to form a fused solid. The fused solid is dissolved in water to solubilize the tungsten and rhenium values and then pass through an anion exchange resin to remove the rhenium values and form a solution containing the tungsten values. The resin is stripped to obtain the rhenium values from the resin.

Abstract: In a process is disclosed for recovering rhenium from tungsten and rhenium bearing material by oxidizing and fusing the starting material, solubilizing the tungsten and rhenium values, passing the resulting solution through a strongly basic anion exchange resin to retain the rhenium, removing the rhenium from the resin with an organic stripping liquid of tributylphosphate and hydrochloric acid, washing the remaining rhenium off the resin with water, combining the water and organic to form a two phase system in which the organic phase contains the major portion of the rhenium, and contacting with aqueous ammonia to strip values.