Abstract: The invention is directed to a process and apparatus for dissolving a molybdenum core wire in a tungsten filament coil which comprises reacting the filament coil in a sealed reaction vessel fitted with at least one liquid trap with an acid mixture containing nitric acid, sulfuric acid and water in the presence of an oxygen containing gas wherein the amount of the oxygen containing gas is controlled by a liquid level sensing device attached to the liquid trap. The invention enables efficient conversion of nitrogen oxide gases to nitric acid and recovery of molybdenum from the reaction vessel.

Abstract: Solid solutions of titanium, a second metal such as niobium, vanadium, and molybdenum and a third metal such as cobalt, germanium, or iron, wherein the second metal is niobium or vanadium and optionally when the second metal is molybdenum, react rapidly at room temperature obviating the need for a high temperature induction period. Solid solutions having formula (Ti.sub.1-x Nb.sub.x).sub.1-y M.sub.y wherein 0.25.ltoreq.x.ltoreq.0.95 and wherein y varies from at least about 0.01 to the solubility limit of M such as cobalt, germanium, or iron in said solution, are also disclosed. Hydrides of solid solution alloys of Ti/Mo/M, Ti/Nb/M and Ti/V/M are also disclosed.

Abstract: There is provided an improved process for the chlorination of particulate titaniferous ores using a particulate reactive carbon in a fluidized bed. The particulate reactive carbon is lignite char.

Abstract: A process was developed to optimize the thallium (III) produced by the reaction of hydrogen peroxide and thallium (I). In the optimized process, thallium (III) is removed from the reaction mixture during the oxidation reaction.

Abstract: A process is described whereby gadolinium and gallium containing by-products can be reprocessed to yield the oxides of these elements in sufficient purity to be re-used in the process for manufacturing Gd.sub.3 Ga.sub.5 O.sub.12 (GGG) single crystal boules thereby improving the economics of production of GGG wafers significantly. The gadolinium and gallium oxides are recovered and separated from transition metal impurities introduced during fabrication of GGG wafers by precipitating the gadolinium as oxalate which is thereafter pyrolyzed to gadolinium oxide and eluting the gallium containing filtrate over an ion exchange resin and precipitating therefrom as an oxalate the gallium present. The gallium precipitate is also pyrolyzed to the gallium oxide. The process can be extended to include purification and re-use of by-products generated in other grinding and polishing operations which may result in the recycling of the order of 80% of the generated by-products.

Abstract: A process was developed using hydrogen peroxide for the oxidation of thallium (I) to thallium (III) in a solvent at a pH of 9.0 or less. Any convenient solvent may be used, such as water, acetic acid, methanol, or a mixture of solvents. Optionally, a buffered solvent may be used.

Abstract: This invention concerns a process for extracting chromium (III) from an aqueous solution containing chromium (III) with an extractant comprising a mixture of mono-2-ethylhexyl phosphoric acid and di-2-ethylhexyl phosphoric acid. An organic solvent such as a low aromatic kerosene is employed in this invention for dilution and dissolution of the extractant. Aqueous acid waste streams containing chromium (III) can be reduced to a chromium (III) concentration of 80 ppm thereby enabling the stream to be reclaimed.

Abstract: A process for the preparation of pentavalent vanadium compounds by reprocessing acid extracts of vanadium-containing catalysts spent in the hydrotreatment of crude or residual oils, characterized in that extracts containing trivalent and tetravalent vanadium are oxidized at a pH between 0.5 and 2.6 with an oxygen-containing gas to form concentrates of tetravalent vanadium, after which oxidation is carried out at a pH between 2.6 and 4.0 with an oxygen-containing gas to form concentrates of pentavalent vanadium and in that solid vanadium compounds are subsequently recovered by separating them from the liquid phase.

Abstract: A process for producing titanium tetrachloride in which iron-titanium ore is leached in hydrochloric acid to produce a solid phase comprising upgraded titanium-containing material, and a spent liquid phase. Dissolved metal chlorides in the spent liquid phase are regenerated to produce hydrochloric acid in an acid regeneration zone. The titanium-containing material is chlorinated to produce a product stream containing titanium tetrachloride and entrained solids, including metal chloride. The entrained solids are recovered from the product stream and the metal chloride portion thereof is recycled to the acid regeneration zone.

Abstract: A method of recovering metal values from an aqueous stream. The metal values are preferably obtained from leaching spent hydroprocessing catalysts, and include nickel, cobalt, vanadium and molybdenum. The metal values are extracted, isolated and purified by liquid, liquid extraction techniques.

Abstract: A method of stripping an organic extraction solvent containing quaternary alkyl ammonium complexes. The extraction solvent is contacted with an aqueous stripping solution having at least 75 g/l bicarbonate ion, while maintained at between pH 7 and 9 at a temperature of no more than 50.degree. C.

Abstract: There is disclosed a method for the treatment of aluminum dross oxides which contain aluminum metal, aluminum carbide, aluminum nitride and salts such as potassium and sodium chloride. The method comprises the thermal treatment of an aqueous suspension of the dross oxides with agitation in the presence of a particulate grinding medium. The method is practiced in a stirred reactor vessel which contains a bed of refractory, ceramic balls that are agitated with a slurry to provide a sufficient abrading action on the aluminum metal particles to remove the aluminum hydroxide coating and continually expose the aluminum metal for reaction with the water. This invention comprises the introduction of a purge gas into the suspension, preferably air, during its thermal treatment to reduce the formation of foam during the treatment and to assist in liberation of ammonia formed by the decomposition of the aluminum nitride.

Abstract: A process for separating metal values from an aqueous stream containing vanadium, molybdenum, nickel and cobalt. Vanadium is first precipitated, and then nickel, cobalt, and molybdenum are removed by serial ion exchange.

Abstract: In a process for recovering refractory metal values from a refractory metal carbide cemented with a metal binder. The coated cemented carbide is treated with sulfuric acid to deteriorate the coating.

Abstract: A process for enhancing recovery of cobalt from spent hydroprocessing catalysts when the spent catalyst particles are first roasted at between 400.degree. C. and 600.degree. C. and then contacted with a first aqueous solution of ammonia and an ammonium salt to recover nickel, cobalt, molybdenum and vanadium. The once-leached spent hydroprocessing catalysts are contacted with a second aqueous solution of sulfur dioxide. The metal values are precipitated with hydrogen sulfide and the precipitate is roasted with unroasted spent hydroprocessing catalysts.

Abstract: A process for recovering soluble uranium with an anion exchange system from carbonate-containing water. The process includes means for overcoming the deleterious effects upon the ion exchange system of carbon dioxide gas resulting from the carbonate-contents of the water in the presence of an acidic elutriate.

Abstract: A process for obtaining molybdenum as a useful product from aqueous solutions to be purified, according to claim 1 of French patent No.

Abstract: A procedure is given for recovering yttrium and europium from phosphors or solutions which have become contaminated. An acid solution containing the yttrium, europium and impurities is passed through a cation resin exchange column until there is no longer a difference between the contaminated and effluent liquids. Yttrium and europium are then stripped from the resin exchange column using a concentrated hydrochloric acid solution. The hydrochloric acid solution containing the yttrium and europium is heated with oxalic acid to produce yttrium and europium oxalate and the oxalate is fired to produce yttrium and europium oxide.

Abstract: A method of treating sulphidic mattes containing from 5% to 60% iron; from 15% to 40% sulphur together with soluble non-ferrous metals such as copper, cobalt, nickel and zinc and also optionally insoluble non-ferrous metals which term includes platinum group metals gold and silver by a leaching process to effect substantial separation of the non-ferrous metals from iron as well as from insoluble residue material. The matte is contacted in a finely subdivided form with sulphate in acid medium at a temperature of from 70.degree. C. to 120.degree. C. and an oxygen partial pressure of from 50kPa to 1,000kPa. The quantity of sulphate present is at least the stoichiometric amount required for dissolving the soluble non-ferrous metals present but is limited to ensure that a substantial proportion of iron which dissolves simultaneously with the soluble non-ferrous metals precipitates out as it is replaced by dissolving non-ferrous metals.

Abstract: Chromium trioxide is made by reacting sodium dichromate with sulphuric acid in an aqueous reaction mixture, evaporating the resultant liquor to cause crystallization of most of the chromium trioxide and to cause the concentration of sodium sulphates to be close to but below that at which sulphate crystals start to form, and separating the chromium trioxide crystals from the evaporated liquor. The liquor may then be cooled so as to cause crystallization of sodium sulphates, generally as sodium bisulphate, and the resultant liquor, after separation of the crystals, may be recycled to the reaction mixture containing dichromate and sulphuric acid.