Abstract: A method for preparing a redox flow battery electrolyte is provided. In some embodiments, the method includes the processing of raw materials containing sources of chromium ions and/or iron ions. The method further comprises the removal of impurities such as metal ions from those raw materials. In some embodiments, a reductant may be used to remove metal impurities from an aqueous electrolyte containing chromium ions and/or nickel ions. In some embodiments, the reductant is an amalgam. In some embodiments, the reductant is a zinc amalgam. Also provided is a method for removing ionic impurities from an aqueous acid solution. Further provided a redox flow battery comprising at least one electrolyte prepared from the above-identified methods.

Abstract: The invention relates to a method for removing chloride from zinc sulphate solution in conjunction with zinc production. According to the method, the chloride is removed from solution by means of monovalent copper, which is produced in a separate copper(I) oxide formation stage, in which the pH is regulated to the region of 4.5-5.

Abstract: The disclosure provides to a PDC element protective system including a mask configured to protect a non-leached portion of a leached polycrystalline diamond compact (PDC) element during a leaching process. The mask may be formed from or coated with polytetrafluoroethylene (PTFE). The disclosure also provides a leaching system containing such a mask and a leaching vessel as well as methods of using the protective and leaching systems. The disclosure further provides a Lewis acid-based leaching agent and methods of its use. Finally, the disclosure provides a method of recycling a PDC or carbide element using a Lewis acid-based leaching agent.

Abstract: The invention relates to a method for the removal of metal impurities in chloride-based copper recovery processes. The amount of impurities in a strong chloride solution of monovalent copper can be reduced according to the method down to very low levels by using ion exchange as at least one purification stage.

Abstract: A process for recovering a target metal from an oxidized metalliferous material comprises the steps of: in an acid generation stage, adding sulfuric acid to a solution comprising a metal halide to generate an acidic aqueous halide solution; in a leaching stage that is separate to the acid generation stage, leaching the oxidized metalliferous material with the acidic aqueous halide solution to leach the target metal into solution; passing the solution from the leaching stage to a target metal recovery stage in which the target metal is recovered from the solution while the metal halide is retained in solution; and returning the solution with the metal halide therein from the target metal recovery stage to the acid generation stage.

Abstract: Pyrophoric nanoparticles and methods of producing the same are provided herein. An exemplary method of producing pyrophoric nanoparticles can include providing a first aqueous solution comprising at least one metal salt and an aliphatic polyether; providing a second solution comprising a metal hydride reducing agent; continuously combining the first and second solutions to produce nanoparticles in a liquid phase; separating the nanoparticles from the liquid phase; and drying the nanoparticles to form pyrophoric nanoparticles. The pyrophoric nanoparticles can have a diameter ranging from about 1 nm to about 50 nm.

Abstract: Dispersed, crystalline, stable to oxidation copper particles are prepared in the absence of polymeric dispersants by rapidly reducing a Cu(I) salt with an Fe(II) carboxylic acid complex in water. The resulting microns sized copper powders contain only organics which decompose at temperatures low enough not to interfere with sintering processes and the formation of conductive copper structures.

Abstract: A system which uses available waste acid process streams from hydrometallurgical extraction processes as absorption media for the direct production of leach grade acid solutions for return to the hydrometallurgical processing circuit for use in liberating metals from metal-bearing materials. The produced acid may have a concentration in the range suitable for processing of metal-bearing materials.

Abstract: A method for detoxifying spent CCA (copper, chromium, arsenic) treated wood, from which CCA is efficiently removed from the wood, allowing both the CCA and the wood to be reused has been developed. The method comprises the steps of (1) microwave-enhanced acid extraction of CCA, (2) separation of the acid-containing CCA solution from the wood, (3) separation/precipitation of CCA from the acid extract, (4) recovery and regeneration of CCA-bearing precipitant for reuse in the wood preservation industry, (5) recycling recovered acid solution, (6) microwave-assisted liquefaction of the extracted wood, and (7) use of detoxified liquefied wood to form polymeric materials such as polyurethanes and phenolic resin adhesives. The recovered CCA may be used to treat wood. The recovered acids may be used to extract CCA from CCA-treated wood, and the liquefied wood may be used as phenolic or polyurethane resins.

Abstract: A system and process for recovering copper from a copper-containing ore, concentrate, or other copper-bearing material to produce high quality cathode copper from a leach solution without the use of copper solvent/solution extraction techniques or apparatus. A process for recovering copper from a copper-containing ore generally includes the steps of providing a feed stream containing comminuted copper-containing ore, concentrate, or other copper-bearing material, leaching the feed stream to yield a copper-containing solution, conditioning the copper-containing solution through one or more physical or chemical conditioning steps, and electrowinning copper directly from the copper-containing solution in multiple electrowinning stages, without subjecting the copper-containing solution to solvent/solution extraction prior to electrowinning.

Abstract: Methods and systems for removing copper minerals from a molybdenite concentrate. One embodiment provides leaching copper from the molybdenite concentrate with a leaching solution comprising ferric chloride, removing molybdenite from the leaching solution, introducing an acid into the leaching solution and introducing O2, O3, or a combination of both, into the leaching solution. A method for regenerating ferric chloride in a leaching solution is also provided. One embodiment provides adding a leaching solution comprising Fe(II) ions, Fe(III) ions, or a combination of both, to a mixture of mineral sulfides, introducing an acid into the leaching solution, and introducing O2, O3, or a combination of both, into the leaching solution.

Abstract: A method for preparing a redox flow battery electrolyte is provided. In some embodiments, the method includes the processing of raw materials containing sources of chromium ions and/or iron ions. The method further comprises the removal of impurities such as metal ions from those raw materials. In some embodiments, a reductant may be used to remove metal impurities from an aqueous electrolyte containing chromium ions and/or nickel ions. In some embodiments, the reductant is an amalgam. In some embodiments, the reductant is a zinc amalgam. Also provided is a method for removing ionic impurities from an aqueous acid solution. Further provided a redox flow battery comprising at least one electrolyte prepared from the above-identified methods.

Abstract: A process for recovering copper from an acid aqueous solution containing cupric chlorides and alkali metal and/or alkali earth metal chlorides by a solvent extraction with a cation-exchange extractant, comprising the step of processing a solvent extraction in the presence of sulfate ions.

Abstract: A process for the recovery of gold from a potassium iodide-iodine solution is provided. The gold is precipitated from the solution using a weak acid, (e.g. ascorbic acid), a buffer, (e.g. sodium bicarbonate), and a dye. The precipitate is then removed from the solution resulting in the recovery the gold precipitate and the potassium iodide-iodine solution.

Abstract: A process for recovering nickel and cobalt values from nickel- and cobalt-containing laterite ores as an enriched mixed nickel and cobalt sulphide intermediate and for producing nickel and cobalt metal from the nickel and cobalt sulphide intermediate. The laterite ore is leached as a slurry in a pressure acid leach containing an excess of aqueous sulphuric acid at high pressure and temperature, excess free acid in the leach slurry is partially neutralized to a range of 5 to 10 g/L residual free H2SO4 and washed to yield a nickel- and cobalt-containing product liquor, the product liquor is subjected to a reductant to reduce any Cr(VI) in solution to Cr(III), the reduced product liquor is neutralized to precipitate ferric iron and silicon at a pH of about 3.5 to 4.0, and the neutralized and reduced product liquor is contacted with hydrogen sulphide gas to precipitate nickel and cobalt sulphides.

Abstract: A method for producing a copper/palladium colloid catalyst useful for Suzuki couplings.

Abstract: The present invention discloses a process for producing nanometer powders, comprising the following steps: (a) providing reactant solution A and reactant solution B that can rapidly react to form precipitate; (b) continuously adding said solution A and solution B into a mixing and reacting precipitator with a stator and a rotor in operation, respectively; and (c) post-treating the precipitate-containing slurry discharged continuously from the mixing and reacting precipitator. The present process could produce nanometer powders with adjustable particle size, good homogeneity in size and good dispersity. The method also has the characteristics of high production yield, simplicity in process and low consumption of energy. It could be applied to produce various nanometer powders of metals, oxides, hydroxides, salts, phosphides and sulfides as well as organic compounds.

Abstract: A method of recovering precious metal values from refractory sulfide ores is provided. The method includes the steps of separating clays and fines from a crushed refractory sulfide ore, forming a heap from the refractory sulfide ore, producing a concentrate of refractory sulfide minerals from the separated fines and adding the concentrate to the heap, bioleaching the heap to thereby oxidize iron sulfides contained therein, and hydrometallurgically treating the bioleached ore to recover precious metal values contained therein.

Abstract: The present invention is directed to a system for recovering metal values from metal-bearing materials. During a reactive process, a seeding agent is introduced to provide a nucleation site for the crystallization and/or growth of solid species which otherwise tend to passivate the reactive process or otherwise encapsulate the metal value, thereby reducing the amount of desired metal values partially or completely encapsulated by such material. The seeding agent may be generated in a number of ways, including the recycling of residue or the introduction of foreign substances. Systems embodying aspects of the present invention may be beneficial for recovering a variety of metals such as copper, gold, silver, nickel, cobalt, molybdenum, zinc, rhenium, uranium, rare earth metals, and platinum group metals from any metal-bearing material, such as ores and concentrates.

Abstract: The present invention is directed to a process for recovering metal values from metal-bearing materials. During a reactive process, a seeding agent is introduced to provide a nucleation site for the crystallization and/or growth of solid species which otherwise tend to passivate the reactive process or otherwise encapsulate the metal value, thereby reducing the amount of desired metal values partially or completely encapsulated by such material. The seeding agent may be generated in a number of ways, including the recycling of residue or the introduction of foreign substances. Processes embodying aspects of the present invention may be beneficial for recovering a variety of metals such as copper, gold, silver, nickel, cobalt, molybdenum, zinc, rhenium, uranium, rare earth metals, and platinum group metals from any metal-bearing material, such as ores and concentrates.

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: The invention relates to a method for processing residues containing at least one non-ferrous metal, preferably chosen from the group comprising zinc, lead, nickel, copper and cadmium and/or compounds thereof. According to this method, the non-ferrous metal is extracted from the residues by an extracting agent containing a carboxylic acid and/or a substituted carboxylic acid and/or its alkali salts and/or ammonium salts and/or mixtures thereof.

Abstract: The present invention is directed to a process for recovering metal values from metal-bearing materials. During a reactive process, a seeding agent is introduced to provide a nucleation site for the crystallization and/or growth of solid species which otherwise tend to passivate the reactive process or otherwise encapsulate the metal value, thereby reducing the amount of desired metal values partially or completely encapsulated by such material. The seeding agent may be generated in a number of ways, including the recycling of residue or the introduction of foreign substances. Processes embodying aspects of the present invention may be beneficial for recovering a variety of metals such as copper, gold, silver, nickel, cobalt, molybdenum, zinc, rhenium, uranium, rare earth metals, and platinum group metals from any metal-bearing material, such as ores and concentrates.

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 hydrometallurgical method involves treating a dross source containing typically both antimony and tin and treating the dross to a series of chemical operations to yield a soft lead precursor, suitable for making soft lead for lead-based alloys for batteries or other applications, which method includes utilizing sulfuric acid to decompose the dross source to provide a slurry in which the liquid contains the principal tin values and the solid phase contains the antimony and lead values, followed by treating of the separated solid phase so as to either separate the lead values from the antimony values via an antimony leach and a solid/liquid separation or by desulfurizing the solid phase, carrying out a solid/liquid separation, treating the solid phase with a lead leach to solubilize the lead values and carrying out a further solid/liquid separation to recover the lead-rich phase as the filtrate, separated from the antimony-rich solid phase.

Abstract: The invention relates to a method for producing copper in a hydrometallurgical process from copper-bearing raw materials, such as sulfidic concentrates. The concentrate is leached in a leaching stage of several steps into a chloride-based solution. The copper-bearing solution obtained from this leaching is subjected to reduction and solution purification, whereafter the copper contained in the solution is precipitated as copper oxidule by means of alkali hydroxide. The alkali chloride solution formed in the production of copper oxidule is fed into chloride alkali electrolysis, where it is regenerated back into alkali hydroxide. The hydrogen generated in the electrolysis is used in the reduction of copper oxidule and in other reduction stages of the process. The formed chlorine is used in the leaching of the raw material. When necessary, the reduced copper that is in a granular or pulverous form is further subjected to melting and casting in order to produce commercial-grade copper.

Abstract: A method of processing a copper mineral, the method comprising activating the copper mineral by milling the copper mineral to P80 of between 2 and 20 micron, and subsequently subjecting the activated copper mineral to an oxidative hydrometallurgical treatment in the presence of chloride ions in an amount of from 2 to 10 g/L.

Abstract: A method for concurrently transporting and leaching metal values from an ore or concentrate containing said metal values from an originating site such as an elevated site to a delivery site comprising the steps of crushing and/or grinding the ore or concentrate to form a particulate having a size range suitable for transport by gravity or a combination of pumping and gravity as a solid constituent in an aqueous slurry, forming an aqueous slurry of from about 30 to about 70 percent by weight of said particulate in an aqueous medium, and adjusting said aqueous slurry to contain an effective amount of a lixiviant for dissolution of said metal values into the aqueous medium.

Abstract: A method for the reclamation of zinc, lead, tin, cadmium and copper from dust containing such elements or compounds which involves leaching the dust with sulfuric acid or ammonium bisulfate, neutralization the leachate with zinc oxide or zinc hydroxide, and cementing and/or roasting various intermediate and final products for the reclamation of the above metals. The method is especially designed for reclaiming the above metals from waste streams from production processes for electrical conductors. The method is a continuous process with the recirculation of various solutions remaining after the completion of each step.

Abstract: After optional preliminary treatment, solid wastes are processed in accordance with the flowsheet FIG. 1: first, Cu is leached selectively with a leaching solution containing Cu(II) ammine as a leachant according to the autooxidation or the autocatalytic action which proceeds depending on the equations: ##STR1## and the Cu(II) ammine concentrated in the leaching solution is extracted with a solvent Lix-54; thereafter, Cu.sup.2+ is stripped so that it moves into a Cu electrolyte and Cu electrowinning is performed to have metallic Cu deposited at the cathode, with the total process being carried out in a closed circuit. By this process, copper and other nonferrous metals can be selectively recovered from motor scrap and shredded solid wastes such as abandoned automobiles and home electric appliances in a simple and economical manner.

Abstract: A hydrometallurgical process for recovering copper from copper bearing ores or fractions, by a process of first wetting and sulfatizing the ore with controlled amounts of H.sub.2 SO.sub.4 and water, followed by acid curing and repulping to sulfatize a substantial portion of the copper in the ore. Also, the fine and coarse fractions can be classified, followed by pile leaching the coarse fraction, preferably reusing the cycled H.sub.2 SO.sub.4 solution obtained during the copper recovery process. Since the coarse fraction is classified from the fine fraction, the pile leaching process is performed at very high specific flows, which substantially reduces the leaching period as compared with that of conventional pile leaching.

Abstract: A process for the extraction of copper from a sulphide copper ore or concentrate comprises the steps of subjecting the ore or concentrate to agitation leaching at an elevated temperature and pressure to obtain a resulting acidic leach liquor containing dissolved copper and reducing the acidity of the resulting acidic leach liquor by effecting percolation leaching of a bed of low-grade copper ore or granular rock with the acidic leach liquor. The agitation leaching is carried out in two stages, i.e. a first leaching step at an elevated temperature and pressure in the presence of oxygen and an acidic chloride solution as lixiviant and a second leaching step at atmospheric pressure with an acidic sulphate solution. In a preferred embodiment, the bed of low-grade copper ore or granular rock is in the form of a heap and the percolation leaching comprises heap leaching. Copper is extracted from the leach liquor by solvent extraction.

Abstract: A process for the extraction of copper from a copper ore or concentrate comprises first subjecting the ore or concentrate to agitation leaching at an elevated temperature and pressure in the presence of oxygen and water to obtain a resulting acidic leach liquor which contains dissolved copper. The acidity of the resulting acidic leach liquor is then reduced by affecting percolation leaching of a bed of low grade copper ore or waste rock with the resulting acidic leach liquor, whereby the pH of the leach liquor is raised, for example to a value of about 1.5 to 2. In a preferred embodiment the bed of low grade ore or waste rock is in the form of a heap and the percolation leaching comprises heap leaching.

Abstract: Heavy metal ions react with ferrous dithionite in acidic aqueous solution. They are reduced to metallic particles that are suitable for recycling and reuse when recovered from the acidic water. When chelating agents are present, they are deactivated by bonding to the ferrous ions. Ferrous dithionite, (FeS.sub.2 O.sub.4) is either generated in-situ or ferrous ions and dithionite ions can be provided by other methods.

Abstract: A process for recovering copper from cupric ion containing aqueous solutions which comprises adding to the aqueous solution containing cupric ions an amount of reducing agent which corresponds from 0.1 to 10 moles of reducing agent per mole cupric ion, and heating the reaction mixture in the absence of oxygen in a closed vessel to a temperature of from 170.degree. to 240.degree. C., said reducing agent being one or more members of the group consisting of:(a) organic aldehydes RCHO (R=H, C.sub.1 to C.sub.5 alkyl)(b) carboxylic acids R COOH (R=H, linear or branched C.sub.1 to C.sub.5 alkyl)(c) hydroxycarboxylic acids R.sub.1 COOH (R.sub.1 =HO(CH.sub.2).sub.n, CH.sub.3 CH(OH)--, CH.sub.3 (CH.sub.2).sub.n, CH(OH)-- with n=1 to 3)(d) dicarboxylic acids R.sub.2 COOH (R.sub.2 =HOOC(CH.sub.2).sub.n with n=1 to 3)(e) amino acids R.sub.3 COOH (R.sub.3 =CH.sub.3 (CH.sub.m CH(NH.sub.2)-- (CH.sub.3).sub.2 (CH).sub.m CH(NH.sub.2 -- with m=1 to 3, CH.sub.3.CH(OH)(NH.sub.2), HOO C.CH(NH.sub.2).(CH.sub.2).sub.

Abstract: A method for waste treating metal containing solutions comprising decomposing the metal from the solution in the substantial absence of air and separating the decomposed (precipitated) metal from the solution.