Abstract: A process for extracting metal values from aqueous solutions of metal salts which comprises the steps of contacting the aqueous solution with a solution in a water-immiscible organic solvent of one or more o-hydroxyaryloximes containing at least 3 aliphatic or alicyclic carbon atoms and which are strong metal extractants and one or more alkylphenols optionally containing one chlorine atom or one cyano group, separating from the aqueous phase the solvent phase containing metal in the form of a complex with the o-hydroxyaryloxime contacting the solvent phase with an aqueous mineral acid, and separating the solvent phase from the aqueous phase containing metal in the form of a salt with the mineral acid.

Abstract: A process for removing zinc from an aqueous solution of a nickel salt by liquid-liquid extraction using as the extraction agent an organic phosphoric acid dissolved in an organic solvent, adding a strongly oxidizing substance at an elevated temperature to the aqueous phase emerging from the extraction to precipitate the cobalt as a hydroxide and decompose the organic phase left in the aqueous phase and to adsorb it into the cobalt hydroxide precipitate, and finally separating it from the pure aqueous nickel salt solution.

Abstract: Zinc is recovered from a material containing zinc and iron. The material is leached with sulphuric acid to produce a final pH of 3-5.5. Zinc powder is added to the leaching solution to precipitate polluting metals. Zinc is now extracted with a solution of a dialkyl phosphoric acid in an organic solvent. Zinc is extracted from the organic solution with sulphuric acid. Zinc is recovered from the sulphuric acid solution as metal or as zinc sulphate.

Abstract: Novel 2-hydroxyiminoacetic acids of the formula ##STR1## where R is an aromatic hydrocarbyl group substituted with one or more aliphatic chains of at least four carbon atoms are excellent for the extraction of metal values from acidic metal - containing aqueous solutions, particularly for the separation of Cu from Fe, Ni from Co and Ca from Mg.

Abstract: Process for the recovery of the zinc contained in the residual solutions obtained after electrolytic deposition by fixing the zinc (none of the other metals present in the solution being included in said complex), in the form of a complex by adding of a alkaline metal halide (sodium chloride preferred) to the residual solution adjusted to a low acidity, for example, by dialysis. The process permits the almost total recovery of zinc, and a large part of sulfuric acid.

Abstract: New chelate exchange resins capable of selective recovery of copper, nickel, and other valuable metals from an acidic aqueous leach liquor are prepared by reacting a crosslinked haloalkyl polymer matrix resin (I) with certain aminopyridines (II) to give a resin (III) ##STR1## with pendent methyleneaminopyridine groups attached to the matrix resin. Particularly useful resins are obtained by reacting chloromethylated styrene-divinylbenzene copolymer beads with an aminomethylpyridine, such as 2-picolylamine, N-methyl-2-picolylamine, N-(2-hydroxyethyl)-2-picolylamine, N-(2-methylaminoethyl)-2-picolylamine, or bis-(2-picolyl)amine. At a typical copper ore leach liquor pH of about 2, the picolylamine resins will absorb 15-30 mg copper/ml resin with a 5-10 fold selectivity for copper over ferric iron.

Abstract: A hydrometallurgical process for the separate recovery of non-ferrous, ferrous, and precious metal values and sulfur from metal sulfide ore concentrates by leaching of metal sulfides with a lixiviant containing ferric chloride, cupric chloride and chlorine, precipitating cuprous chloride from the leach solution with butadiene, separating and decomposing the formed addition compound to recover the cuprous chloride, oxidizing and hydrolyzing the cuprous chloride to precipitate cupric oxychloride, converting the cupric oxychloride to cupric oxide, and reducing the cupric oxide with hydrogen for the recovery of copper. The leach residue is treated for the recovery of elemental sulfur and gold. Brine solution resulting from the conversion of cupric oxychloride to cupric oxide is electrolyzed for the production of sodium hydroxide for the cupric oxychloride conversion, hydrogen for the cupric oxide reduction and chlorine, which is partly used in the recovery of gold and partly recycled to the concentrate leach.

Abstract: Process of extracting metals using organic solvent solutions of salts of hydrogen ion exchange agents and quaternary ammonium compounds. Organic solvent solutions of such quaternary ammonium salts of hydrogen ion exchange agents.

Abstract: Zinc values are leached or converted in a solution containing excess SO.sub.2 or HSO.sub.3.sup.- ions, selectively extracted from that solution into an organic phase containing organo acid phosphates and stripped from the organic phase for further processing.

Abstract: Copper and silver are recovered from complex sulfide ores or concentrates containing, in addition, metals such as lead, zinc, arsenic, antimony, and iron by leaching with a combination of ferrous chloride and oxygen.

Abstract: Optionally substituted benzimidazoles containing an alkyl or cycloalkyl group in position 1 and containing at least 5 alkyl or cycloalkyl carbon atoms extract metals from aqueous solutions of their salts into water-immiscible organic solvents in presence of halide ion. Benzimidazoles having a branched-chain alkyl group of at least 7 carbon atoms in position 1, and especially mixtures of such compounds, are most effective. The benzimidazoles are particularly useful for extracting cobalt selectively from mixtures of cobalt and nickel salts. The metals can be recovered from the organic solvent by extraction into water free from halide ion.

Abstract: The ore is subjected to nitric acid leaching and the leach solution is heated to a temperature at which one of the additional sulfur and iron values is selectively insolubilized with respect to the solution, while the other is maintained in solution for subsequent separation from the liquor after the insolubles have been removed and the liquor has been neutralized. In addition, in one embodiment of the invention the heating and acid neutralization steps are controlled within certain prescribed limits to make it possible to remove the metals from the liquor by solvent extraction without the problem of lasting precipitates forming in the liquor and fouling the extraction process. Where there is a sizable amount of dissolved iron in the liquor, the liquor may be subjected to autoclaving at a temperature above about 149.degree. C (300.degree. F) to precipitate the iron as the oxide thereof. This effect is possible even where the liquor is high in sulfate concentration.

Abstract: Metal ions may be scavenged from solution by means of a complexing agent comprising an inorganic substrate, such as a clay mineral, with covalent organic molecules, such as onium compounds, chemically bonded to the substrate, the covalent organic molecules containing free coordinating groups. The complexing agents are particularly useful in scavenging environmentally harmful metal ions such as mercury from industrial effluents.

Abstract: A process for producing a spherical chelating resin is disclosed. In the production, a prepolymer is prepared in the absence or presence of a solvent by subjecting a poly-N-substituted polyamine having at least two residual active hydrogen atoms bonded to nitrogen atoms or a poly-N-substituted polyalkylene imine having at least two residual active hydrogen atoms bonded to nitrogen atoms to a poly-addition reaction with an epoxy compound having at least two epoxy groups. The prepolymer is cured by heating and agitating a suspension of the prepolymer in an aqueous solution of a water-soluble high polymer or a nonionic surfactant in the absence or presence of known curing agents for epoxy resins. The resulting spherical cured resin is subjected to a saponification reaction or to a reaction with a hydrazine or a polyamine, and then a spherical chelating resin is obtained.

Abstract: The method comprises the steps of crushing of the ore, neutralization by a mixture of water and sulphuric acid, introduction of a controlled quantity of sulphur dioxide gas at a pH value between 1.5 and 4 for promoting dissolution of nickel, copper and a desired quantity of manganese, leaching of the ore with sulphuric acid at a pH value between 1 and 3 for selectively dissolving the nickel and copper, separation of the solid and liquid phases, and separation of the metals contained in the liquid phase.

Abstract: Metal values are extracted from manganiferous ocean floor nodule ore by treating the ore with hydrochloric acid, thereby producing chlorine and a starting pulp containing a solution of the metal chlorides and a solid residue. The starting pulp is subjected to at least two subsequent acidifications with HCl, each acidification being followed by addition of fresh ore, thereby producing chlorine and a final pulp containing a concentrated solution of metal chlorides and a solid residue. The solid residue is separated from the concentrated solution and substantially all the metal values, except manganese and alkali and alkaline earth metals, are separated from the solution. The manganese is separated from the solution by treatment with chlorine, at least the major portion of which was produced in the preceding leaching steps, while maintaining the solution at a pH of between about 3 and 7 by addition of a neutralizing agent such as MgO or Mg(OH).sub.2 whereby the manganese is precipitated in the form of MnO.sub.

Abstract: A method is described for the efficient stripping of stable complexes of a selected quaternary amine and a cyanide of Zn or Cd. An alkali metal hydroxide solution such as NaOH or KOH will quantitatively strip a pregnant extract of the quaternary ammonium complex of its metal and cyanide content and regenerate a quaternary ammonium hydroxide salt which can be used for extracting further metal cyanide values.

Abstract: Salicylaldoximes having a total of at least three alkyl carbon atoms contained in one or more nuclear substituents are used to extract metals from aqueous solutions of their salts as complex compounds soluble in water-immiscible organic solvents. The salicylaldoximes are prepared from the corresponding salicylaldehydes by reaction with hydroxylamine.

Abstract: 5-Heptyl-2-hydroxybenzaldoximes in which the heptyl group is attached to the benzene ring through a tertiary carbon atom and particularly mixtures of such aldoximes are effective as extractants for metals such as copper from aqueous solutions. These aldoximes have a more rapid rate of metal transfer from aqueous to organic phase, and vice versa, than other alkylhydroxybenzaldoximes. The benzaldoximes may be prepared from the corresponding aldehydes by reaction with hydroxylamine.

Abstract: Zinc is extracted from aqueous ammoniacal solutions using fluorinated .beta.-diketones of the structure ##STR1## where n is a whole integer of 1 to 4, m is 0, 1 or 2 and R is an alkyl group of 1-25 carbons, the R group or groups providing requisite solubility in liquid hydrocarbon solvents.

Abstract: An improved liquid-liquid extraction process for separating metals from each other in which an aqueous solution containing metals is mixed with an organic solution containing an extraction agent that releases hydrogen ions. A mixture of aqueous dispersed phase and an organic continuous phase is formed and the pH of the aqueous dispersed phase is controlled by the addition of a neutralizing agent to the mixture of the aqueous dispersed phase and the organic continuous phase on the basis of pH measurements made with pH electrodes immersed in the mixture of the phases. These direct measurements permit accurate adaptation of the rate of addition of the neutralizing agent to the rate at which hydrogen ions are being released so that the pH of the aqueous dispersed phase is kept substantially constant. The phases are separated from each other after transfer of metal ions from the aqueous to the organic phase, and the separated metal values are recovered.

Abstract: A method is provided for processing raw manganese nodules for the selective recovery of metal values of nickel, copper, cobalt and zinc contained therein by hydrometallurgical means. The raw nodules are suspended in water or dilute wash solution to form a suspension. The suspension and sulfuric acid are charged to a pressure vessel to provide a solid-liquid suspension of nodules and leach solution. The solid-liquid suspension of nodules and leach solution is heated in the pressure vessel to a temperature between about 150.degree. C and about 300.degree. C to cause the nickel, copper, cobalt and zinc to be selectively leached from the nodules into the leach solution to form a metal rich leach solution containing these metals and a residue, with the solid-liquid suspension having a sulfuric acid content of less than 35 g/l upon completion of the leaching. The metal rich leach solution containing nickel, copper, cobalt and zinc is separated from the residue.

Abstract: Process for extraction and separation of metals utilizing the advantages of liquid-liquid extraction with cation exchangers without requiring the equivalent addition of alkali. The process is based on a combination of leaching the metal-containing raw materials with an organic acid (cation exchanger) and a subsequent use of the formed metal cationic complex in a liquid-liquid extraction process. In the said extraction process, the organic solution of metal complexes is used to recover and separate metal ions from an aqueous solution of metal salts.

Abstract: A process is described for recovering metals which are present in aqueous solution as complex metal ammine ions having an ammonia co-ordination of at least two. According to the process, the complex metal ammine bearing solution is contacted with a cationic ion exchange resin in the ammonium form to effect loading of the complex metal ammine ions from the solution onto the resin. The loaded resin is then stripped by contacting it with a controlled volume of aqueous ammonium salt stripping solution having an ammonium ion concentration of at least two molar. The free ammonia and ammonium salt concentrations in the stripping solution are controlled such that the controlled volume of stripping solution is effective to substantially completely strip the free ammonia and metal values from the resin.

Abstract: The recovery of non-ferrous transition metals such as copper and nickel from acidic hydrometallurgical leach liquors with a 2-picolylamine chelate exchange resin is improved by the in situ reduction of Fe.sup.+.sup.3 present in the leach liquor with a water soluble reducing agent during the resin loading cycle. The chelate resin functions not only as a selective sorbent for the desired metal values, but also as a catalyst for the in situ reduction of Fe.sup.+.sup.3 to Fe.sup.+.sup.2. A suitable reducing agent such as SO.sub.2 or HCHO is fed into the chelate resin column with the leach liquor. When the loading cycle is completed, regeneration with sulfuric acid gives an enriched eluent with a high non-ferrous metal:Fe ratio. For example, using SO.sub.2 with a copper leach liquor feed, subsequent regeneration at about 70.degree. C gives better than 90 percent recovery of the copper as a highly enriched copper sulfate solution with a Cu:Fe ratio of about 10,000.

Abstract: The invention concerns new, crosslinked, macroporous, vinyl-aromatic plastic materials containing thiourea groups, to processes for their production and to their use for adsorbing metal compounds, especially noble metal and mercury compounds.

Abstract: A process for separating zinc and copper values from an aqueous solution of copper and zinc salts having a pH of between about 0.5 and 6 is provided comprising:A. contacting said aqueous solution with the copper salt of di-(2-ethylhexyl) phosphoric acid to form a zinc-containing organic phase and a copper-containing aqueous phase;B. separating said zinc-containing organic phase from said copper-containing aqueous phase; andC. stripping said organic phase to form a solution of a zinc salt and di-(2-ethylhexyl) phosphoric acid.

Abstract: A hydrochloric acid leach solution is subjected to a first cycle of extraction by an organic solvent, solvent washing and stripping so that the stripping liquor contains iron, zinc, cadmium and gallium while the liquor constituted by the first raffinate at the outlet of the extraction unit mainly contains nickel, cobalt and copper. In a second extraction cycle, the stripping liquor contains copper while the second raffinate mainly contains cobalt and nickel. In a third extraction cycle, the stripping liquor contains cobalt while the third raffinate mainly contains nickel.

Abstract: An improvement in the process of extracting metal from aqueous acidic solution using a quaternary ammonium thiocyanate extractant wherein a special amount of thiocyanate ion is introduced into the aqueous solution prior to or contemporaneously with the extraction. Results achieved are better extractions with little or no additional loss of thiocyanate ion in the aqueous raffinate.

Abstract: A pollution-free process for the recovery of high purity zinc from zinc containing material including sulfide ores which provides for maximum conservation and re-use of reagents, the process consisting of chlorinating the materials either with ferric chloride or chlorine gas followed by selective removal of metals other than zinc by standard procedures, such as, lead chloride crystallization, cementation, etc. to produce a solution containing essentially only zinc chloride and ferrous chloride. To enhance the purity of the zinc end product zinc chloride is separated from the ferrous chloride solution with a zinc selective extraction agent from which the zinc chloride is stripped with sodium chloride solution in a sodium chloride stripping circuit followed by precipitation of zinc as the carbonate.

Abstract: Process for recovery of zinc and other metal values from zinc waste or other metal waste containing chlorine and/or other anions forming undesirable metal salts. The waste is leached with a liquid organic phase containing a cation exchanger. The impurities are removed from the organic phase with water, and the zinc and other metal values are extracted from the organic phase with mineral acid. Thereafter the zinc and other metal values can be recovered with known methods.