Abstract: A method of processing intermediate nickel bearing products, the method comprising subjecting the intermediate nickel bearing products to an acid leach in order to dissolve substantially all of the acid soluble magnesium bearing minerals contained therein to provide an upgraded nickel bearing residue and a leach solution. The method is particularly suitable where the intermediate nickel bearing products are nickel sulphide concentrates or nickel iron oxide calcine.

Abstract: A method and apparatus for recovering lead from scrap lead/acid batteries involves first mechanically breaking up the batteries into small pieces, then feeding the small pieces into a substantially vertical, upwardly diverging separation/leaching column through which ammoniacal ammonium sulphate solution (AAS) passes upwardly at a speed that allows the removal of metallic lead and lead alloys as sinks from the bottom of the column, with comminuted case material floating up and out of the column, while the lead compounds remain in suspension in the column for lead sulphate dissolution. The insoluble lead dirxide from the pastes is removed from the AAS downstream of the column and is slurried with sulphuric acid to convert the lead dioxide to lead sulphate, which is then returned to the separation/leaching column. The clarified AAS is fed to an electrowinning tank where metallic lead is plated out.

Abstract: Recovery of cerium values from fluoride-containing ores such as bastnasite is enhanced. The ore is ground, roasted, and leached with dilute hydrochloric acid to produce an ore concentrate. The concentrate is treated with a solution of hydrochloric acid and boric acid to solubilize cerium values and convert fluoride to tetrafluoroborate ion. Tetrafluoroborate is removed from the solution, e.g., by precipitation, and the solution is further processed for recovery of cerium values. Removal of tetrafluoroborate avoids loss of cerium as insoluble cerium tetrafluorborate during said further processing.

Abstract: Process for beneficiating titanium bearing ore selected from the group consisting essentially of titaniferous ores, leucoxene, rutile, perovskite, and sphene comprising:(a) contacting said ore with an aqueous solution of a mineral acid having a concentration of about 3-30 percent by weight said contacting taking place at a temperature of about 160.degree.-300.degree. C., until the desired amount of impurities are solubilized and a leachate is formed,(b) removing the leachate from the product of step (a).

Abstract: An improved extraction system employing a quaternary amine to extract anions from an aqueous solution, particularly precious metals such as gold or silver from an aqueous alkaline solution. The improvement comprises the use of a weak organic acid (a compound providing an acidic proton) along with the quaternary amine. The improvement is useful in both liquid-liquid and liquid-solid extraction systems.

Abstract: A method is provided for the recovery of precious metals, such as gold and silver, from refractory carbonaceous sulfidic material. The carbonaceous sulfidic material is ground and placed in heaps or piles or pulped or slurried and bioleached to oxidize the sulfide minerals using bacteria at temperatures from about 15.degree. C. and up to about 40.degree. C. The biooxidized residue is then treated using a specific microbial consortium, or a product of the microbial consortium, at temperature from about 5.degree. C. to 40.degree. C. to deactivate the carbonaceous component of the material to prevent binding of the precious metal to the carbonaceous component. The precious metal liberated in the residue remaining from the biological oxidation of sulfide and deactivation of carbon are recovered by dissolution.

Abstract: A process for extracting and purifying the gallium contained in an industrial solution of sodium aluminate by fixing the gallium on a stationary phase constituted by porous polystyrene adsorbent resin which is impregnated with an extracting agent, optionally in the presence of a surface-active agent. After elution of the gallium in acid medium, the resultant gallium salt is purified and concentrated so as to be reduced directly to the state of high purity metallic gallium, by electrolysis.

Abstract: In a process for the hydrometallurgical treatment of electric arc furnace dusts which includes an acetic acid leach, the acetic acid solution used to perform the leach is made strong enough to dissolve heavy metal residues in the dusts, the iron-containing residues of which are recycled to a steel producing furnace. Zinc and other heavy metals are precipitated from hot acetic acid solution as useful products by the use of hydrogen sulphide. Calcium is then precipitated from the acetic acid solution as a clean gypsum using a deficiency of sulphuric acid, thus avoiding leaving sulphate ions in solution in sufficient concentration to interact with the dust and form sulphates in the iron containing residues when the acetic acid is recycled to the leaching step.

Abstract: A process for extracting metal values such as gallium and/or indium from aqueous solutions by contacting said solutions with a water immiscible organic solvent having dissolved therein a heterocyclic thione.

Abstract: A process for the removal of cadmium ions by liquid-liquid extraction from wet process phosphoric acid, which had been obtained from crude phosphate ores by dissolution with sulfuric acid, uses salts of long chain alkyl amines or ammonium bases with the chlorocomplexes of polyvalent metal ions, which are dissolved in an inert organic solvent.

Abstract: Coating with high-melting metals can be simplified by alloying high-melting metal with sufficient aluminum to make low-melting alloy that is applied, bonded in place, and then subjected to the leaching out of some or most of the aluminum. The resulting surface is porous and will receive and hold top coatings. Leached surface can be pyrophoric and top coating can be exothermically combustible. Pyrophoric powder can also be coated on boron or carbon fibers or sintered with combustible particles. Carbon can be kept from contaminating diffusion-treated workpieces, by conducting diffusion treatment in retorts containing little or no carbon. Porosity can be created by subjecting workpiece to diffusion conditions in contact with depleting material such as powdered nickel or high-nickel aluminides or cobalt or high-cobalt aluminides. Aluminum particles can be electrophoretically deposited on foil and then diffused in. Leaching aluminum out with caustic is improved when a little H.sub.2 O.sub.

Abstract: A process of refining zinc oxide from roasted zinc sulphide bearing concentrates comprises leaching the concentrate in an aqueous sulphur dioxide solution under controlled conditions providing selective separation of zinc from other elements contained in the concentrate. The zinc bisulphite solution so obtained is separated from the remaining solids and is heat treated, preferably with steam, to precipitate zinc monosulphite crystals, possibly after first adding zinc dust to the solution to cement out residual copper and cadmium. The zinc monosulphite is then separated from the solution, possibly washed with water, and calcined to yield purified zinc oxide.

Abstract: Rare earth values are nonpollutingly recovered from a rare earth mineral/ore, especially one containing but minor amounts of the rare earths, by (a) leaching/decomposing such rare earth mineral/ore with a solution of nitric acid to solubilize the rare earth values contained therein, (b) optionally separating insoluble residue from the resulting leach solution, (c) separating the rare earth values from the leach solution, (d) treating the leach solution thus stripped of rare earth values with a hydroxide of a metallic cation M to precipitate solubilized impurities and separating the thus precipitated impurities therefrom, (e) treating the resulting purified solution with sulfuric acid to precipitate metal sulphates and separating the thus precipitated sulfates therefrom to regenerate the above nitric acid solution, and (f) optionally recycling such regenerated solution of nitric acid to the leaching/decomposition step (a).

Abstract: A method is provided for removing chromium from a chromium containing waste material wherein the waste material is dried by indirect heating, sized to a particle size of less than 0.105 mm, mixed with alkaline and oxidizing reactants, and reacted in a reaction vessel by indirect heating using approximately the stoichiometric oxygen requirement to form a reaction material containing water soluble chromates. The reaction material is cooled and resized, and then subjected to an aqueous solvent extraction to produce a solid phase containing substantially no chromium and an aqueous phase containing water soluble chromates. This aqueous phase is subjected to evaporation resulting in a concentrated chromate phase. The waste material has been rendered non-hazardous and the chromium has been recovered as useful chromates.

Abstract: An apparatus for use in bioleach processing of metal-bearing solids is disclosed. The apparatus includes a containment means adapted for containing a slurry made up of metal-bearing solids, a predetermined quantity of water, oxygen, carbon dioxide, nutrients and a species of microorganisms capable of oxidizing some portion of the metal-bearing solids and obtaining energy for growth from that oxidation. The apparatus further includes a plurality of horizontally oriented porous, flexible membrane diffusers adapted for introducing oxygen into the bottom of the reactor vessel in the form of small widely dispersed bubbles.

Abstract: A process for recovery of gallium from aqueous solution containing gallium by adsorbing gallium to a chelate resin is disclosed. According to this process, the aqueous solution containing gallium is contacted batchwise with a chelate resin having a high selective adsorptivity for gallium or by flowing the aqueous solution through the resin at a rate of at least 20 parts by volume/hr of the aqueous solution per 1 part by volume of the resin.

Abstract: A process for eliminating an industrial waste sludge by converting its metal values into useful products involves the selective leaching of Mn, divalent Fe, and other valuable metals, such as Sc, Co, Cr, Ni, Th, rare earths, etc. with a mixture of dilute sulfuric acid and a reductant at ambient temperature. Scandium is recovered by passing the leachate through an ion exchange column which is packed with a weakly cationic resin. The retention of other metals on the resin column is negligible. The scandium is eluted from the resin column and converted to a solid product. The raffinate from the ion exchange column is titrated with an alkali solution to convert the metals, except divalent Mn and Fe, to a solid metal hydroxide. After the separation the filtrate is treated with an alkali and an oxidant to recover iron as a solid product of iron oxide which is separated from the solution.

Abstract: Precious metal values, particularly gold and silver, are liberated from refractory, carbonate ores by adjusting the molar ratio of sulfide to total acid consumers to between about 1.2 and about 3.2 in the ore feed to a pressure oxidation process. The ore is contacted with oxygen to oxidize sulfide in the ore with at least about 65 percent of the sulfide oxidation occurring in a first oxidation zone at a temperature above about 360.degree. F. The oxidation of sulfide forms at least about 5 grams of free sulfuric acid in the first oxidation zone. The oxidation process is continued in subsequent oxidation zones. A gas stream is removed from the oxidation zones and oxygen is separated from carbon dioxide and other inerts in the gas stream and the purified oxygen is recycled to the oxidation zones.

Abstract: A process for the hydrometallurgical recovery of metal value, particularly copper, from copper-containing sulphide materials in which the material is conventionally ground and reacted with a solution containing less than 3 moles per liter of chloride ion, and optionally as little as 15 g/liter, together with sulphate ions with continuous oxygen injection and vigerous agitation. The reacting may be carried out at a pH in the range of 0.5-4, at moderate pressure as low as atmospheric pressure and at a moderate temperature below the boiling point of the solution such as 85.degree. C.

Abstract: Methods are disclosed for recovering one or more of the metals of tungsten and molybdenum from metal-cellulose material. One method involves digesting the material in a mineral acid selected from the group consisting of hydrochloric acid having a concentration of at least about 4 normal, and sulfuric acid having a concentration of at least about 9 normal at a temperature of at least about 50.degree. C. for a sufficient time to form a digestion solid containing the major portion of the tungsten and a digestion solution containing a portion of any molybdenum which is present in the material, and separating the solid from the solution. Another method involves having as the starting material a metal-cellulose material comprising one or more of the metals of tungsten and molybdenum and elements selected from the group consisting of arsenic, phosphorus, silicon, and combinations thereof.

Abstract: A metal is dissolved by being brought into contact with at least one halogenated hydrocarbon in the presence of a cationic surfactant.