Abstract: Selective extraction of a metal anion complex, such as a platinum-group metal halide, from an aqueous solution containing other metal anions or anion complexes, by contacting the solution with a diquaternary ammonium salt having two quaternary nitrogens spaced at a distance less than about 10 ?, selectively binding the metal anion complex to the diquaternary ammonium salt to form an organo-metallic complex, and separating the organo-metallic complex from the solution. Alternatively, the diquaternary ammonium salts may be adsorbed or chemically bonded to a substrate, and the metal anion complex-containing solution passed over the substrate. Preferably, the two quaternary nitrogens are spaced a distance apart that is complementary to the ionic diameter of the target metal anion complex.

Abstract: A method of treatment or purification of a molybdenum concentrate also containing copper, comprises the step of subjecting the molybdenum concentrate to pressure oxidation in the presence of oxygen and a feed solution containing copper (e.g. CuSO4) and halide (e.g. CuCl2) to produce a pressure oxidation solution containing copper and a solid residue containing molybdenum. The pressure oxidation solution may be combined with feed solution to a second pressure oxidation in which a copper concentrate is treated for the recovery of copper therefrom.

Abstract: Nanoparticle compositions of noble metals, and methods of making them, are described. The nanoparticle compositions are made by reacting a salt or complex of a noble metal, such as Au, Ag, Cu or Pt, with a weak ligand, and a reducing agent, in a single liquid phase. The noble metal is typically provided as a halide or carboxylate. The ligand is preferably a fatty acid or aliphatic amine. The reducing agent is preferably a borohydride reagent, hydrazine, or a mixture thereof. Nanocrystals in the size range of 1 nm to 20 nm are produced, and can be made in substantially monodisperse form.

Abstract: A separation medium, a method for using that separation medium and an apparatus for selectively extracting multivalent cations such as pseudo-lanthanide, prelanthanide, lanthanide, preactinide or actinide cations from an aqueous acidic sample solution is described. The separation medium is preferably free-flowing and comprises particles having a diglycolamide (DGA) extractant dispersed onto an inert, porous support.

Abstract: The present invention provides a method for selectively removing metal ions of interest from a solution (12), such as the wastewater from a chemical mechanical polishing process. The method comprises contacting a solution (12) containing solid particles, an oxidizing agent and a first concentration of the metal ions with an ion-exchange resin (20), such as a crosslinked poly-4-vinylpyridine resin, that is resistant to damage by the oxidizing agent and that is operative when in contact with the solution (12) to exchange selected ones of the metal ions in the solution for selected preferred ions in the ion-exchange resin thereby to produce a treated solution (22) having a second concentration of the metal ions that is lower than the first concentration. The present invention also relates to an apparatus (100) and system (500) for use with the method of the present invention.

Abstract: A display device is formed by burying at least part of a light emitting device in an insulating material, wherein a drive electrode for the light emitting device is formed so as to be extracted on a surface of the insulating material. A display unit is produced by two-dimensionally arraying such light emitting devices on a base body. Since the display device is modularized by burying a light emitting device finely formed in an insulating material, to re-shape the light emitting device into a size easy to handle, it is possible to suppress the production cost of the display unit using such display devices, and to ensure a desirable handling performance of the light emitting device; for example, facilitate the carrying of the light emitting device or the mounting thereof on a base body.

Abstract: The present invention provides a method for selectively removing metal ions of interest from a solution (12), such as the wastewater from a chemical mechanical polishing process. The method comprises contacting a solution (12) containing solid particles, an oxidizing agent and a first concentration of the metal ions with an ion-exchange resin (20), such as a crosslinked poly-4-v resin, that is resistant to damage by the oxidizing agent and that is operative when in contact with the solution (12) to exchange selected ones of the metal ions in the solution for selected preferred ions in the ion-exchange resin thereby to produce a treated solution (22) having a second concentration of the metal ions that is lower than the first concentration. The present invention also relates to an apparatus (100) and system (500) for use with the method of the present invention.

Abstract: The preparation of concentrated solutions of oxime metal extractants, such as aldoximes and ketoximes, or mixtures of aldoxime and ketoxime, and the use thereof in formulating or preparing extraction reagent compositions for use in an extractant organic phase in a process of extracting metals from aqueous solutions containing metal values; and in particular, to concentrates which are solutions of individual ketoxime or aldoxime or mixtures of water-insoluble hydroxy aldoximes and ketoximes, in varying ratios by weight of 1:100 aldoxime to ketoxime, or conversely, 100:1 ketoxime to aldoxime, in water-immiscible hydrocarbon solvents or equilibrium modifiers. The invention also provides for maintaining stability of concentrates determined by accelerating rate calorimetry to define the ranges of oxime concentration and volume whereby the concentrate will be a stable, flowable, pourable and pumpable concentrate which can be safely stored long term.

Abstract: A method of recovering base metal from a tailings dump which includes the steps of: aerating a surface layer of the dump; adjusting the pH and the moisture content of the surface layer to provide conditions favourable for bacterial oxidation of sulphide minerals; allowing bacterial oxidation to take place for a controlled period, after the controlled period removing the oxidized surface layer and adding water thereto for form a slurry; separating the slurry into solids and a solution; and recovering base metal from the solution.

Abstract: A silica-polyamine based extraction material removes selected transition metal ions from solution in the presence of iron ions. The silica-polyamine base is a reaction product of a polyamine and a covalently anchored trifunctional hydrocarbylsilyl that yields non-crosslinked amino groups to which pyridine function group is attached. The extraction material is particularly useful in selectively removing copper from low concentration, low pH leach solutions separating copper from ferric iron or chloride ions. The product is a durable, high capacity extraction material that selectively captures copper at high flow rates and releases that copper into highly concentrated solutions.

Abstract: A process for recovering cyanide from feed material containing cyanide and copper involves the steps of: (a) contacting the feed material with a strong base anion exchange resin whereby copper and cyanide from the feed material are adsorbed onto the resin; (b) contacting the resulting resin with an eluant solution containing free cyanide ion to elute copper and cyanide from the resin; (c) separating the eluted resin from the eluting solution or eluate from step (b); (d) acidifying the eluate from step (b) to precipitate copper; (e) separating the acidified solution from the precipitate in step (d) and alkalizing directly or after concentration the separated solution containing HCN; (f) contacting the eluted resin from step (b) with an acid to condition the resin and remove additional cyanide while leaving most of the copper in the resin phase; (g) converting the HCN solution formed in step (f) to cyanide ion, directly or after concentration of the HCN solution, by the addition of alkali; and (h) returning the

Abstract: The invention generally relates to a process for the recovery or removal of metal species from a solution or slurry comprising the steps of: a) contacting the solution or slurry with a polymeric material, selected from the group consisting of a solid superhydrophilic polyurethane polymer containing a chelating and/or solvating agent, a water-insoluble polymeric chelating agent dispersed in a water-insoluble carrier solution, and a water-soluble polymeric chelating or co-ordinating agent to load the polymeric material with metal species wherein said polymeric material; b) separating the loaded polymeric material from the solution or slurry; and c) recovering or removing the metal from the polymeric material. There is also considered a polymeric material for use in the recovery of metal species from a solution or slurry, the polymeric material comprising a solid superhydrophilic polyurethane polymer containing a chelating or co-ordinating agent and/or a solvating agent.

Abstract: Selective extraction of one or more metal anions from an aqueous solution, by contacting the aqueous solution with an organic solution including a diquaternary amine, wherein the diquaternary amine has two diquaternary nitrogens spaced at a distance of less than about 10 ?, selectively binding the metal anions to the diquaternary amine, and then separating the organic solution from the aqueous solution, wherein the diquaternary amines having the selectively bound metal anions are concentrated in the organic solution. Alternatively, the diquaternary amines may be adsorbed or chemically bonded to a solid, and the metal anion-containing aqueous solution passed over the solid having the diquaternary amines. Palladium may be selectively extracted by contacting the acidic solution with an iodide and an organic solvent, allowing the palladium to bind to the iodide, and then separating the organic solution from the aqueous solution, concentrating the bound palladium ions in the organic solution.

Abstract: A substituted thiourea having the general formula characterized in that each of R1 and R2 independently comprises an alkyl, alkaryl or aryl group or a substituted derivative thereof, and contains at least one fluorine atom, and in that each of R3 and R4 is selected from the group which consists of H, alkyl, alkaryl and aryl and substituted derivatives thereof, including fluorine-containing derivatives. A method for producing the substituted thiourea is disclosed, and a method for extracting a noble metal such as gold from a matrix by treating the matrix with the substituted thiourea is also disclosed.

Abstract: A method for producing an indium-containing aqueous solution having a reduced amount of metal impurities is provided. A method for producing an indium-containing aqueous solution having a reduced amount of metal impurities which comprises bringing an aqueous solution containing indium and metal impurities whose hydrogen ion concentration is adjusted at 0.5 mol/L to 3 mol/L into contact with a non-chelate ion-exchange resin to remove the metal impurities, and a method for producing an indium-containing aqueous solution having a reduced amount of metal impurities which comprises bringing an aqueous solution containing indium and metal impurities into contact with a chelate ion-exchange resin to remove the metal impurities are provided.

Abstract: A solvent extraction composition is comprised of one or more orthohydroxyarylaldoximes and one or more othohydroxyarylketoximes, and one or more equilibrium modifiers in an amount providing a degree of modification of the orthohydroxyarylaldoximes from about 0.2 to 0.

Abstract: A low viscosity water insoluble extraction reagent composition according to the invention is comprised of: (a) an extractant selected from the group consisting of an aldoxime, a ketoxime, or a combination thereof; (b) an equilibrium modifier having a Brookfield viscosity of equal to or less than about 5 centapoise at 25° C. and a flash point equal to or greater than about 141° F. wherein the molar ratio of modifier to extractant is from about 0.05 to about 2.0 so as to provide a net copper transfer greater than that achieved in the absence of modifier. Such low viscosity extractants afford higher recoveries of copper, permit reduced equipment size such as smaller mixers and settlers and the use of reduced amounts of less overall organic inventory.

Abstract: The present invention allows the determination of trace levels of ionic substances in a sample solution (ions, metal ions, and other electrically charged molecules) by coupling a separation method, such as liquid chromatography, with ion selective electrodes (ISE) prepared so as to allow detection at activities below 10−6M. The separation method distributes constituent molecules into fractions due to unique chemical and physical properties, such as charge, hydrophobicity, specific binding interactions, or movement in an electrical field. The separated fractions are detected by means of the ISE(s). These ISEs can be used singly or in an array. Accordingly, modifications in the ISEs are used to permit detection of low activities, specifically, below 10−6M, by using low activities of the primary analyte (the molecular species which is specifically detected) in the inner filling solution of the ISE. Arrays constructed in various ways allow flow-through sensing for multiple ions.

Abstract: A solvent extraction composition is provided which comprises one or more orthohydroxyarylaldoxime or orthohydroxyarylketoxime and at least one dialkyl ester of an optionally substituted ethylene or polyethylene glycol and preferably a water immiscible organic solvent. The orthohydroxyarylaldoximes, or orthohydroxyarylketoximes commonly are of Formula (1), wherein R1 is hydrogen or a hydrocarbyl group, and R2 is an ortho-hydroxyaryl group; and the dialkyl esters of an optionally substituted ethylene or polyethylene glycol commonly are of Formula (2), wherein R7 and R8 are each independently an optionally substituted alkyl group; R9 to R20 are each independently hydrogen or optionally substituted hydrocarbyl; m, n and p are each independently 0, 1, 2, 3 or 4 provided that m+n+p is greater than or equal to 1; and q is 1, 2 or 3.

Abstract: A solvent extraction composition is provided which comprises one or more orthohydroxyarylaldoximes or orthohydroxyarylketoximes and one or more esters substituted with a hydroxyl group, and preferably a water immiscible organic solvent. The orthohydroxyarylaldoximes, or orthohydroxyarylketoximes commonly have Formula (1), wherein R1 is hydrogen or a hydrocarbyl group, and R2 is an ortho-hydroxyaryl group; and the esters substituted with a hydroxyl group are of Formula (2), wherein one of R7 or R8 is a substituted hydrocarbyl group with at least one hydroxyl group and the other is an optionally substituted hydrocarbyl group. Preferred orthohydroxyarylaldoximes are 5-(C9 to C14 alkyl)-2-hydroxybenzaldoximes and preferred orthohydroxyarylketoximes are 5-(C9 to C14 alkyl)-2-hydroxyacetophenone oximes. Preferred esters substituted with a hydroxy group are highly-branched alkyl esters comprising from 5 to 51 carbon atoms, wherein the hydroxy group resides on R8.

Abstract: The invention relates to a method for extracting copper in liquid-liquid solvent extraction from aqueous solutions with a high sulphate content, by raising the viscosity of the extraction solution and by dispersing the aqueous solution into drops, achieving a dense drop aggregation. The viscosity of the extraction solution may be raised either by increasing the content of the actual extractant, the extraction reagent, in the extraction solution or by using a diluting agent with a higher viscosity than that of the diluting agent normally used. By raising the viscosity of the extraction solution the mixing durability of the extraction dispersion can be increased and resulting of that the amount of residual drops is decreased. Other advantages are that the extraction solution flow of the extraction process decreases in relation to the flow of the aqueous solution acting as the copper source and that the size of the extraction equipment needed is reduced.

Abstract: A process for the extraction of a base metal such as Ni, Co or Zn, from a sulphide ore or concentrate containing copper and the base metal comprises the step of subjecting the ore or concentrate to pressure oxidation in the presence of oxygen and an acidic solution containing halide and sulphide irons to produce a product solution containing copper and the base metal. The product solution is subjected to a copper extraction process for recovering copper from the solution and the product solution containing the base metal after copper recovery is recirculated or recycled to the pressure oxidation to effect build-up of the base metal in the product solution. Preferably, a stream which is split from the product solution is treated for the recovery of the base metal.

Abstract: A process for the recovery of copper from a copper-containing aqueous acid leach solution containing nitrate ions, in which the leach solution is contacted with a solution of an oxime extractant in a water-immiscible organic solvent, which comprises utilizing at least one of the following process variants: I) using an oxime extractant in the organic solution consisting of oximes selected from the group consisting of at least one ketoxime, and a mixture of at least one ketoxime and at least one aldoxime wherein the ketoxime:aldoxime molar ratio is in the range of from 1:0 to about 1:1.2 II) wherein the organic solution does not contain any modifiers or kinetic additives for the oxime extractant; III) reducing the acidity of the acid leach solution to a pH in the range of from about 2.25 to about 3.1, preferably from 2.25 to 2.7, prior to contact with the organic solution; and IV) reducing the electromotive force in the leach solution to less than about 550 mV prior to contact with the organic solution.

Abstract: The present invention relates generally to a process for recovering copper and other metal values from metal-containing materials through pressure leaching operations. In accordance with the various aspects of the present invention, metal-containing pregnant leach solutions from pressure leaching operations need not be significantly diluted to facilitate effective metal recovery using solvent extraction and electrowinning.

Abstract: Processes for recovering gold from copper-gold ores thiosulfate leaching or gold ores copper catalyzed thiosulfate leaching using ion exchange technology are disclosed. The processes include subjecting the gold-bearing and copper-bearing thiosulfate solution to a pH and/or temperature adjustment to reduce tetrathionate concentration in the thiosulfate solution prior to contacting with an ion exchange resin. The ion exchange resin once loaded with gold and optionally copper is eluted with a mixture of sodium tetrathionate, ammonium thiosulfate and sodium sulfite. Gold and optionally copper are recovered from the eluate by electrowinning or precipitation.

Abstract: Copper is preferentially extracted from iron in an aqueous feedstock solution containing dissolved copper and iron values by contacting the feedstock solution with a water-immiscible organic solution comprised of a hydrocarbon solvent and a compound of the formula I wherein R5 is a C1-22 linear or branched alkyl group, a C2-22 linear or branched alkenyl group, a C6 aryl group, a C7-22 aralkyl group, a halogen, OH or —OR6 wherein R6 is a C1-22 linear or branched alkyl group, a C2-22 linear or branched alkenyl group, a C6 aryl group, a C7-22 aralkyl group; R1 is hydrogen, or a C1-22 linear or branched alkyl or alkenyl group, a C6 aryl group or a C7-22 aralkyl group; R2-R4 is hydrogen, halogen, a linear or branched C6-12 alkyl group, —OR6 wherein R6 is a C1-22 linear or branched alkyl group, a C2-22 linear or branched alkenyl group, a C6 aryl group, or a C7-22 aralkyl group to form an aqueous phase comprised of iron and an organic phase comprised of the hydrocarbon solvent and a cop

Abstract: An improvement in the solvent extraction process for recovering metal values, i.e. copper, from acidic aqueous solutions containing copper and iron which may also include chloride, and more particularly to an improvement which provides for increased copper to iron ratios in the loaded organic extractant phase. The improvement comprises washing the loaded organic extractant phase prior to stripping of the copper values therefrom with an aqueous acidic wash solution containing at least a portion of electrolyte solution, wherein the wash solution or the electrolyte solution has been previously contacted with copper metal.

Abstract: A process for the recovery of copper from an aqueous phase containing nitrate ions, in which the aqueous phase is contacted with a solution of an oxime extractant in a water-immiscible organic solvent, which comprises using at least one of the following process variants: I) reducing the acidity of the aqueous phase prior to contact with the organic solution; and II) reducing the electromotive force in the aqueous phase prior to contact with the organic solution.

Abstract: A method of treatment or purification of a molybdenum concentrate also containing copper, comprises the step of subjecting the molybdenum concentrate to pressure oxidation in the presence of oxygen and a feed solution containing copper (e.g. CuSO4) and halide (e.g. CuCl2) to produce a pressure oxidation solution containing copper and a solid residue containing molybdenum. The pressure oxidation solution may be combined with feed solution to a second pressure oxidation in which a copper concentrate is treated for the recovery of copper therefrom.

Abstract: A process for the recovery of gold and the platinum group metals from sources that contain relatively low amounts of the metals is described. The process is environmentally acceptable and uses no expensive and potentially dangerous organic solvents.

Abstract: The present invention provides a method for selectively removing metal ions of interest from a solution (12), such as the wastewater from a chemical mechanical polishing process. The method comprises contacting a solution (12) containing solid particles, an oxidizing agent and a first concentration of the metal ions with an ion-exchange resin (20), such as a crosslinked poly-4-vinylpyridine resin, that is resistant to damage by the oxidizing agent and that is operative when in contact with the solution (12) to exchange selected ones of the metal ions in the solution for selected preferred ions in the ion-exchange resin thereby to produce a treated solution (22) having a second concentration of the metal ions that is lower than the first concentration. The present invention also relates to an apparatus (100) and system (500) for use with the method of the present invention.

Abstract: The present invention is directed to an improved process for the recovery of metal ions from metal-containing aqueous solutions using a supported liquid membrane (SLM) whereby the pH of the metal-containing solution is preferably adjusted to between 5.5 and 8 and ammonia or other weak base is present in the metal-containing solution in a concentration sufficient to form a complex between the weak base and metal ions present in the solution. The present invention permits enhanced recovery of metal in the solution without any need to adjust the pH of the solution during the SLM process.

Abstract: A processs for the recovery of zinc from a zinc sulphide ore or concentrate comprises the steps of subjecting the concentrate to pressure leaching with an acidic solution containing at least about 15 g/L iron in solution to produce a zinc solution and a solid leach residue containing iron. The zinc solution is subjected to zinc solvent extraction to produce a raffinate and a pregnant zinc solution. A method of removing ion from an iron bearing raffinate is also provided which comprises pressure leaching a zinc sulphide ore with the iron bearing raffinate to produce a solid leach residue containing iron and a zinc solution.

Abstract: A process for the extraction of copper from a sulphide ore or concentrate comprises the steps of subjecting the ore or concentrate to pressure oxidation in the presence of oxygen and an acidic solution containing halide and sulphate ions to obtain a resulting pressure oxidation slurry. The slurry is subjected to a liquid/solid separation step to obtain a resulting pressure oxidation filtrate and a solid residue containing an insoluble basic metal sulphate salt. The basic metal sulphate salt is leached in a second leaching with an acidic sulphate solution to dissolve the basic metal salt to produce a leach liquor containing a metal sulphate, e.g. copper sulphate, in solution and a resulting solid residue. The leach liquor is separated from the solid residue and subjected to a solvent extraction process to produce metal concentrate solution and a metal depleted raffinate. At least a portion of the raffinate is recycled to the pressure oxidation after being subjected to evaporation.

Abstract: A process for the recovery of copper from an aqueous phase containing nitrate ions, in which the aqueous phase is contacted with a solution of an oxime extractant in a water-immiscible organic solvent, which comprises using at least one of the following process variants: I) reducing the acidity of the aqueous phase prior to contact with the organic solution; and II) reducing the electromotive force in the aqueous phase prior to contact with the organic solution.

Abstract: A method of biotreating a solid material to remove an undesired compound using a nonstirred surface bioreactor is provided. According to the method the surface of a plurality of coarse substrates is coated with a solid material to be biotreated to form a plurality of coated coarse substrates. The coarse substrates have a particle size greater than about 0.3 cm and the solid material to be biotreated has a particle size less than about 250 &mgr;m. A nonstirred surface reactor is then formed by stacking the plurality of coated coarse substrates into a heap or placing the plurality of coated coarse substrates into a tank so that the void volume of the reactor is greater than or equal to about 25%. The reactor is inoculated with a microorganism capable of degrading the undesired compound in the solid material, and the solid material is then biotreated in the surface bioreactor until the undesired compound in the solid material is degraded to a desired concentration.

Abstract: A hydrochloric acid solution containing platinum group metals has its acidity adjusted to 5.5 to 6.5M HCl and its redox potential adjusted to at least 500 mV, before being treated by chromatography. Particularly clean separation of at least Pt and Pd can be obtained, and recovered Pt and Pd of at least 99.99% purity may be obtained by following conventional precipitation processes.

Abstract: The present invention relates generally to a process for recovering copper and other metal values from metal-containing materials through pressure leaching operations. In accordance with the various aspects of the present invention, metal-containing pregnant leach solutions from pressure leaching operations need not be significantly diluted to facilitate effective metal recovery using solvent extraction and electrowinning.

Abstract: The present invention provides a novel process for the removal and recovery of metals from waste waters and process streams. The process of the present invention utilizes a combination of a supported liquid membrane (SLM) and a strip dispersion to improve extraction of the target species while increasing membrane stability and reducing processing costs. The process is illustrated with cobalt removal and recovery with unexpected results, such as unexpectedly high cobalt fluxes and a very high cobalt concentration in the strip solution recovered. This process can remove other metals, such as copper, zinc, nickel, mercury, lead, cadmium, silver, europium, lanthanum, neodymium, praseodymium, gadolinium, and selenium, from the feed stream to provide a concentrated strip solution of the target species.

Abstract: A process for recovering gold from thiosulfate leach solutions and slurries in which gold is loaded into an ion exchange resin. Gold is recovered from the resin by elution with polythionate ions and the resin is regenerated with sulfide or sulfite. Gold is recovered from the eluate by precipitation with sulfide ions, cementation or electrowinning. The invention also provides for a process of manufacturing polythionate ion solutions suitable for eluting gold from ion exchange resins.

Abstract: A process for refining noble metals from auriferous mines, wherein the auriferous material is first milled and treated with a cyanide solution, and comprising: a step for the pretreatment of the auriferous material, wherein the complexes of cyanide with noble metals are fixed on anionic resins and then incinerated; a predefining step, which comprises an etching of the materials incinerated during the pretreatment with a hydrochloric-nitric solution; and specific steps for refining the gold, palladium, platinum and silver.

Abstract: Copper is preferentially extracted from iron in an aqueous feedstock solution containing dissolved copper and iron values by contacting the feedstock solution with a water-immiscible organic solution comprised of a hydrocarbon solvent and a compound of the formula I 1

Abstract: A composition for use in extracting metals from aqueous solutions of metals salts comprises at least one o-hydroxyaryloxime containing at least 5 aliphatic or alicyclic carbon atoms and at least one ester containing from 10 to 30 carbon atoms, the weight ratio of o-hydroxyaryloximes to the esters being in the range of 10:1 to 1:3. A process for extracting metal from aqueous solutions using the composition is also disclosed.

Abstract: The invention relates to a method for recovering non-ferrous metals, particularly nickel, cobalt, copper, zinc, manganese and magnesium, from materials containing said metals by converting said non-ferrous metals into sulphates by means of melt and melt coating sulphation, i.e. by a thermal treatment under oxidizing conditions within a temperature range of 400 to 800° C., during which a reaction mixture is formed containing at least one said non-ferrous metal, iron(III)sulphate and alkali metal sulphate, and appropriate reaction conditions are selected to substantially prevent iron(III)sulphate from thermally decomposing to hematite, and finally, said non-ferrous metals are recovered as metallic compounds. In the method of the invention, a process is formed around the melt and melt coating sulphation, which comprises nine steps.

Abstract: The process of the present invention is directed to the use of sulfuric acid and/or an organic acid to regenerate spent sorbent from a metal recovery process. The sorbent can be activated carbon.

Abstract: In an acid leach copper extraction circuit for leaching copper values from copper ores using a water-immiscible organic solvent solution containing a copper extractant and an acid strip solution, the improvement wherein the stripped organic solvent solution is contacted with copper-free fresh aqueous acid to remove additional copper values therefrom, and then the resulting super stripped organic and the copper-containing aqueous acid are sent to the copper extraction circuit.

Abstract: A process is provided for the selective recovery from an impure solution of pure nickel and cobalt solutions, suitable for electrolysis of the respective metals. The impure solution may be that obtained from acid leaching of nickel/cobalt bearing laterite or oxide ore. The impure solution is contacted with a solid ion exchange resin to selectively extract nickel and cobalt, while rejecting at least one element of the group manganese, magnesium, calcium, iron(II), and chromium(III). The ion exchange resin contains bis-picolyl amine as the primary chelating group. The impure solution has sufficiently low levels of chromium(VI) and copper to allow repeated use of the ion exchange resin. The metal-bearing resin is washed and then stripped with an acid solution. This solution is then contacted with a water-immiscible organic phase for the selective extraction of cobalt, leaving nickel in the raffinate as a substantially pure nickel solution.

Abstract: Alternative equilibrium modifiers for use with aldoxime extractants, such as hydroxyl aryl aldoxime extractants, employed in the process for extraction of metal values, particularly copper values, in the extraction from aqueous solutions, in which the extractant and modifiers are employed in an organic solvent phase, the solvent being a water insoluble, water immiscible hydrocarbon solvent, such as a kerosene.

Abstract: An improved process for the extraction of a metal from an aqueous ammoniacal solution comprising: (i) contacting the aqueous ammoniacal solution with an extraction reagent comprised of a water insoluble extractant for the metal, to provide an organic phase, now containing metal values, and an aqueous phase from which metal values have been extracted; (ii) contacting the organic phase with an aqueous stripping solution to provide an aqueous strip phase, now containing metal values, and an organic phase from which metal values have been stripped; and (iii) recovering the metal values from the aqueous stripping solution; the improvement wherein (a) the extraction reagent contains an ammonia antagonist having only hydrogen bond acceptor properties; (b) the stripping solution is an aqueous highly acidic solution; and (c) the organic phase is washed with a weakly acidic aqueous solution prior to stripping with the highly acidic aqueous stripping solution.

Abstract: An ion exchange resin comprising an ion exchange material dispersed or distributed throughout a polyurethane matrix. The ion exchange material is typically a second polymer which has been chemically modified after dispersion or distribution throughout the polyurethane matrix.