Abstract: Gold is recovered from a material including gold and molybdenum or tungsten by contacting the material with an aqueous solution of hydrogen iodide and iodine to solubilize the gold without solubilizing the molybdenum or tungsten and recovering the gold from the solution.

Abstract: Fine metal powder is produced from a wet cobaltic hydroxide precipitate by contacting the precipitate with steam to convert the precipitate to a cobaltous oxide and reducing the cobaltous oxide to produce a fine cobalt metal powder.

Abstract: Tungsten and cobalt metal are recovered from cemented carbides by the electrolytic disintegration of the cemented carbide as the anode in an aqueous electrolyte containing a soluble alkali metal hydroxide. Tungsten carbide is thus converted to carbide particles, which precipitate from the electrolytic solution. The cobalt metal is precipitated in the electrolyte or plated on the cathode. The cobalt metal is then recovered by separation of a cobalt salt, followed by thermal reduction of the salt.

Abstract: In a process for producing fine cobalt metal powder from scrap material containing brazing compositions, the scrap is digested with hydrochloric acid to form a cobalt chloride solution which the silver is removed by precipitation with a suitable alkali metal halide at a pH of about 7 to result in a cobalt amine chloride solution which is further processed to fine cobalt powder.

Abstract: In a process for producing fine size cobalt metal powder from scrap material containing brazing compositions, the scrap is digested with hydrochloric acid to produce an aqueous cobalt acid chloride solution containing copper and silver ions which ions are removed by cementation with iron to result in a cobalt chloride solution which is processed to fine cobalt metal powder.

Abstract: Tungsten is reclaimed from heavy metal alloys of the type having tungsten metal dispersed throughout a matrix material by treating the heavy metal alloy with zinc to form a molten mixture and separating the zinc from the resulting alloy.

Abstract: In a process for producing ammonium metatungstate from ammonium paratungstate, ammonium paratungstate is introduced in the anode chamber of an electrolytic cell which is separated from the cathode chamber by an inert liquid permeable media, when a direct electric current is passed through the cell, ammonium ions migrate to the cathode compartment resulting in an increased concentration of metatungstate in the anode chamber.

Abstract: In a process for preparing ammonium paratungstate from a heavy metal alloy, the metal alloy is introduced as an anode into an electrolytic cell containing an aqueous electrolyte solution comprising ammonium hydroxide and ammonium nitrate. Ammonium paratungstate is formed when a direct electric current is passed through the cell.

Abstract: Cobalt is recovered from byproduct streams from a basic process by contacting the byproduct streams with aluminum metal for a sufficient period of time to produce cobalt metal as a precipitate. The basic process is the type wherein cobalt ions in solution are complexed with ammonia in the presence of halide ions to form an ammine halide solution from which a cobalt containing precipitate is separated. The precipitate is subsequently reduced to form a cobalt metal powder.

Abstract: Fine particle size cobalt metal powder is prepared by treating an aqueous solution of a soluble cobaltic ammine halide with a sufficient amount of a soluble metallic hydroxide to form a cobalt containing precipitate. The precipitate is separated from the solution and reduced in a reducing atmosphere to produce metallic cobalt.

Abstract: The disposition of an array of color phosphor dots on a color cathode ray tube faceplate by conventional photo deposition techniques is facilitated by first coating the individual phosphor particles with polyvinyl alcohol modified with an amino acid such as glutamic or aspartic acid.

Abstract: The disposition of an array of color phosphor dots on a color cathode ray tube faceplate by conventional photo deposition techniques is facilitated by first coating the individual phosphor particles with polyvinyl alcohol modified with an amino acid such as glutamic or aspartic acid.

Abstract: Extra fine cobalt metal powder (up to about 0.8 microns) having less than 100 parts per million cation impurities is produced by a process in which cobalt pentammine chloride is digested in a dilute ammonium hydroxide solution to form a black precipitate, which is separated and heated in a hydrogen atmosphere to reduce the precipitate directly to cobalt metal powder. The cobalt pentammine chloride may be obtained by digesting a cobalt source in hydrochloric acid, adding ammonium hydroxide, oxidizing the cobaltous ion to cobaltic ion, and reducing the pH with hydrochloric acid to less than 1.0 in order to precipitate cobalt pentammine chloride. The final cobalt metal powder is useful, for example, as a starting material in the manufacture of cemented carbides.

Abstract: The disposition of an array of color phosphor dots on a color cathode ray tube faceplate by conventional photo deposition techniques is facilitated by first coating the individual phosphor particles with polyvinyl alcohol modified with an amino acid such as glutamic or aspartic acid.

Abstract: A process suitable for recovering refractory metal carbide values from contaminated uncemented refractory metal carbides containing an iron group metal comprises heating an admixture of the powders of the contaminated refractory metal carbides and glacial acetic acid to the boiling point of the admixture for at least about 30 minutes, the weight of the powders divided by the weight of the acid is less than 5, thereafter removing the resulting carbide solids from the acid and washing the solids with sufficient water to remove the residual acid and drying the solids.

Abstract: Heteropoly acids of tungsten and molybdenum, such as tungstosilicic acid and molybdosilicic acid, are produced by first preparing an aqueous solution of an alkali metal tungstate or molybdate and an alkali metal salt of the hetero atom, and then removing the alkali metal cations from the solution by means of a cation exchange membrane under the influence of an applied electrical potential, whereby the reactive tungstate or molybdate and hetero species anions react to form the desired heteropoly acid.

Abstract: Ammonium tungstate, ammonium paratungstate, ammonium metatungstate or hydrated tungsten trioxide is produced by passing tungstate anions through an anion exchange membrane into an aqueous solution containing ammonium cations under the driving force of an electrical potential for a time sufficient to achieve a pH within the range in which the desired tungsten compound will form.