Abstract: A method of treating a metalliferrous material source is provided. The metalliferrous material source includes at least one of nickel sulphide and cobalt sulphide, and also includes iron sulphide. The metalliferrous material source is leached with a preliminary leachant in a leaching zone to effect production of a preliminary leach product including a preliminary leach solution and a preliminary leach solid residue. The preliminary leachant includes an aqueous solution comprising ammonia and ammonium sulphate. The preliminary leach solution includes at least one of dissolved nickel comprising material and dissolved cobalt comprising material. The preliminary leach solid residue includes: (i) at least one of nickel sulphide and cobalt sulphide, (ii) at least one of other nickel comprising material and other cobalt comprising material, and (iii) other iron comprising material.

Abstract: A method of obtaining copper from feedstock includes: providing feedstock into acid solution including chloride and bromide of one of alkali metal and alkali earth metal, and one of chloride of copper and iron and bromide of copper and iron; leaching monovalent copper and divalent copper with use of oxidizing power of at least one of iron ion and copper ion, with air being blown into the acid solution under an atmospheric pressure at a temperature less than a boiling point of the acid solution; solid-liquid separating the acid solution; blowing air into the solution; oxidizing copper in the solution; coprecipitating iron and impurity; extracting copper from the solution from which deposition including the coprecipitate is separated; obtaining the extracted copper into sulfuric acid solution as copper sulfate; obtaining copper from the copper sulfate; and recycling hydrochloric acid generated in the extracting in another copper leaching.

Abstract: The invention publishes a process to increase the bioleaching speed of ores or concentrates of sulfide metal species in heaps, tailing dams, dumps, or other on-site operations. The process is characterized by the continuous inoculation of the ores or concentrates with isolated microorganisms of the Acidithiobacillus thiooxidans type, together with isolated microorganisms of the Acidithiobacillus ferrooxidans type, with or without native microorganisms, in such a way that the total concentration of microorganisms in the continuous inoculation flow is of around 1×107 cells/ml to 5,6×107 cells/ml. In particular, the invention publishes the continuous inoculation of Acidithiobacillus thiooxidans Licanantay DSM 17318 together with Acidithiobacillus ferrooxidans Wenelen DSM 16786 microorganisms, or with other native microorganisms at a concentration higher than 5×107 cells/ml.

Abstract: A process for the recovery of nickel and/or cobalt from a lateritic ore by heap leaching, the process including the steps of: a) forming one or more heaps from a lateritic ore body wherein that lateritic ore body includes a blend of both limonitic and saprolitic type ores; b) leaching the one or more heaps with a leach solution; and c) recovering the nickel and/or cobalt from the resultant heap leachate.

Abstract: This invention is directed to an improved process for metal recovery from ore using agitation leaching comprising dividing leaching of the crushed and mined ore into at least two sequential leaching-solids-liquid separation-solvent extraction sub-circuits, with no significant dilution during solids-liquid separation in these units, and the raffinate from solvent extraction being recycled back to the leaching, with the underflow pulp from the second liquid-solids separator being sent to a final solid-liquid separator, with water washing, from which the washed solids are sent to disposal and the clarified aqueous wash solution is sent to a final solvent extraction, with some or all of the metal-depleted aqueous raffinate from this final solvent extraction being optionally neutralized, and/or being circulated back to the third solid-liquid separation as wash solution and/or to recovery of other metals and/or to disposal to maximize metal recovery and maintain water balance.

Abstract: A method for selectively recovering a metal from mined ore and other metal-bearing raw source materials is disclosed.

Abstract: Various embodiments provide new methods of rhenium recovery. The methods can include subjecting a metal-bearing solution to an activated carbon bed, and adsorbing rhenium onto the activated carbon. The methods can also include heating a basic aqueous elution solution and eluting the rhenium from the activated carbon with the heated elution solution.

Abstract: The invention relates to a method for recovering gold in connection with the hydrometallurgical production of copper from a waste or intermediate product containing sulphur and iron that is generated in the leaching of the copper raw material. The recovery of both copper and gold occurs in a chloride environment. The gold contained in the waste or intermediate is leached by means of divalent copper, oxygen and alkali bromide in a solution of copper (II) chloride and alkali chloride, in conditions where the oxygen-reduction potential is a maximum of 650 mV and the pH a minimum of 0.5. The bromide accelerates the dissolution of the gold.

Abstract: The mixer apparatus accordant with the invention includes a closed reactor, at least two mixers at different heights, which are on the same shaft, a gas feed pipe below the lower mixer and baffles. The blades of the mixers are mostly rectangular in shape and a minimum of six in number. The angle of inclination of the blades of the lower mixer is around 50-70° and that of the upper mixer around 25-35°. The number of baffles is at least six and their range around 20% of the reactor diameter. The invention is focused also the corresponding method.

Abstract: A method for recovering metal values from refractory sulfide ores is provided. The method includes the steps of separating clays and fines from 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 metal values contained therein.

Abstract: Methods for recovering base metals, including, among other metals, molybdenum and nickel, from metal sulfides containing a Group VIB metal and a Group VIII metal. Generally, the methods comprise: contacting metal sulfides with a leaching solution containing ammonia and air to dissolve the metals into the leaching solution, forming a slurry containing soluble complexes of the metals, ammonium sulphate and solid residue containing ammonium metavanadate and any carbonaceous materials. The solid residue containing ammonium metavanadate and carbonaceous materials is then separated from the slurry and metal complexes are precipitated from the slurry by adjusting the pH. A second slurry may be formed comprising a second solid residue and a primary filtrate comprising ammonium sulfate solution that is substantially free of metals.

Abstract: The process, according to the invention, comprises the following stages: (a) processing (1) of the laterite ore (O) by crushing, scrubbing, attrition, separation, and high-intensity magnetic separation; (b) Leaching (2) of the non-magnetic fraction (CN) obtained form the previous stage (a); (c) optionally, neutralization (3) of the effluent from the leaching and/or solid-liquid separation stages (4); (d) treatment of the effluents from stages (b) or (c) using an ion-exchange hybrid system (5) comprising at least one circuit for removal of impurities and at least one circuit for recovery of nickel and cobalt; (e) elution (6) of the ion-exchange resin used; (f) separation, purification, and recovery (7) of the nickel and cobalt.

Abstract: The present invention is related to an isolated chemolithotrophic bacterium belonging to species Acidithiobacillus thiooxidans named Licanantay, deposited in Deutsche Sammlung von Mikroorganismen and Zellkulturen GmbH-DSMZ with number DSM 17318, and its use in pure form or in mixtures that contains it for bioleaching processes of minerals or sulfured metallic species concentrates. This Licanantay strain DSM 17318 has sulfur-oxidizing activity in both primary and secondary sulfured minerals, especially in the case of chalcopyrite, covellite, bornite, chalcocite, enargite and tennantite.

Abstract: In accordance with the present invention there is provided a method for leaching one or more target metals from an ore, the method comprising the method steps of: curing the ore to be leached through the application of an aqueous solution of a curing agent, producing a cured ore; leaching the cured ore at atmospheric pressure through the application of an ammonium carbonate solution containing free ammonia, producing a pregnant leach solution; and passing the pregnant leach solution to a means for metals recovery.

Abstract: A process for the recovery of nickel and cobalt from laterite ores, the process including the steps of: a) beneficiating the ore to separate it into a beneficiated upgraded ore fraction and a coarse, siliceous low grade rejects fraction which is substantially free from fines and clay materials; b) separately processing the upgraded ore fraction for the recovery of nickel and cobalt; and c) subjecting the low grade rejects fraction to a heap leach process with an acid supplemented solution to create a heap leachate for further nickel and cobalt recovery processing.

Abstract: Provided is a method of easily producing scorodite which is stable and has excellent filtering properties with excellent reproducibility and without using complex operations, when processing arsenic that is included in non-ferrous smelting intermediates, and particularly when processing copper arsenic compounds in the form of an intermetallic compound. Scorodite is produced by a leaching step of leaching arsenic from a non-ferrous melting intermediate containing a copper arsenic compound in the form of an intermetallic compound in the presence of a sulfidizing agent and an oxidizing agent, a solution adjusting step of oxidizing trivalent arsenic to pentavalent arsenic by adding the oxidizing agent to the leaching solution, and a crystallizing step of converting the arsenic in the adjusted solution to scorodite crystals.

Abstract: The invention relates to a method, by means of which the valuable metals contained in a sulphidic, multicomponent concentrate are recovered using hydrometallurgical treatment. One constituent of the concentrate is copper sulphide, which is leached using an alkali chloride-copper (II) chloride solution. The sulphides of other valuable metals, such as zinc, nickel, cobalt and lead are leached before copper leaching and each is recovered as a separate product before copper recovery.

Abstract: A method for manufacturing metal nanoparticles, the method including forming a mixture by dissociating a metallic salt of a metal selected from the group consisting of Ag, Pd, Pt, Au and an alloy thereof as a metal precursor in fatty acid; and adding a metallic salt of a metal selected from the group consisting of Sn(NO3)2, Sn(CH3CO2)2, and Sn(acac)2 as a metallic catalyst into the mixture and mixing the mixture and the metallic salt. According to the method, metal nanoparticles have a uniform particle size distribution and a high yield by performing in a non-aqueous environment without using any organic solvent, and are environmentally friendly due to no use of a reducing agent.

Abstract: It is an object to provide a method and an apparatus for recovering indium, the method and apparatus ensuring that it is unnecessary to recover indium in the form of indium hydroxide, indium can be recovered easily by a filter or the like without handling inferiors and also, the recovery rate of indium is greatly improved. The method includes immersing a precipitation-inducing metal which includes zinc and is made into the form of a solid such that any part coming into view three-dimensionally has a longitudinal length of 2.5 to 10 mm in an etching waste solution containing at least indium and ferric chloride and allowed to stand, thereby allowing indium contained in the etching waste solution to precipitate on the surface of the precipitation-inducing metal based on a difference in ionization tendency between zinc and indium, and detaching the indium precipitated on the surface of the precipitation-inducing metal to recover it.

Abstract: The present invention relates to a method and system for recovery of waste.

Abstract: A heap is constructed with hypogenic copper sulfide bearing ore to include exposed sulfide mineral particles at least 25 weight % of which are hypogenic copper sulfides. The concentration of the exposed sulfide mineral particles is such that the heap includes at least 10 Kg of exposed sulfide sulfur per tonne of solids in the heap. At least 50% of the total copper in the heap is in the form of hypogenic copper sulfides. A substantial portion of the heap is heated to at least 50° C. The heap is inoculated with a thermophilic microorganism, and bioleaching is carried out so that sufficient sulfide mineral particles in the heap are biooxidized to oxidize at least 10 Kg of sulfide sulfur per tonne of solids in the heap and to cause the dissolution of at least 50% of the copper in the heap in a relatively short period of time.

Abstract: An improved method for processing of nickel bearing saprolite and limonite ores to recover the valuable minerals contained therein, comprising leaching the ore with nitric acid to form a slurry; separating the iron values by precipitation, removing the iron values; forming a liquid/solid residue in which nickel, cobalt and magnesium are in solution, and manganese and aluminum are solid residues in oxide form; conducting a liquid-solid separation and removing the solids; and recovering the nickel, cobalt, and manganese from the liquid-metal concentrate. The leachate is recovered and nitric acid from the leachate is recycled.

Abstract: Processes are provided for recovering precious metals from refractory materials using thiosulfate lixiviants. The processes can employ heap leaching or lixiviants that include one or more blinding agents.

Abstract: In a method for leaching gold from copper sulfides, the sulfide ores are first subjected to leaching of copper, thereby producing a leaching residue having 7.9% or less of the copper content. This leaching residue is mixed with a leach liquor, which contains the chloride ion and ferric ion and has 1.9 or less of pH. Gold and copper can be effectively leached from the copper sulfide ores. Ordinarily used oxidizing reagents such as hydrogen peroxide or nitric acid are not used. The gold, copper and iron can, therefore, be leached in a single process and by using an identical leaching liquor. The rate of gold leaching reaction can be enhanced by the co-presence of either copper or bromide ion or both together with the chloride and iron ion.

Abstract: Recovery of nonferrous, rare and precious metals from sulfide minerals and concentrates is described. The hydrometallurgical method of sulfide minerals and concentrates processing, involving sulfide minerals oxidation in aqueous medium using nitrogen oxides, provides that the sulfide materials containing slurry are subjected to oxidation of the sulfide which is realized under controlled conditions of the slurry acidity. Constant neutralization of sulfuric acid formed as a result of the sulfides oxidation is provided. The sulfuric acid is neutralized to acidity level, at which no formation of elementary sulfur occurs, while natural or artificial substances, such as CaC03, MgC03, Ca(OH)2, CaO, NaOH, CaHP04 etc., are used as acidity neutralizers. Oxidation of sulfide minerals is realized under agitation. Oxidation is realized in the range of 20-90° C., mainly in the range of 65-85° C.

Abstract: An improved method for processing of nickel-bearing ores, laterite ores, saprolite and limonite ores, oxidic and sulfide ores, metallurgical wastes, and other metal-bearing materials, to recover the valuable minerals contained therein, comprising comminuting ore to a desired size; leaching the ore at about 70 C to 130 C for about 30 minutes to 4 hours with nitric acid, raising the temperature of the solution to form a liquid/solid residue in which nickel, cobalt and magnesium values are in solution, and iron, manganese, and aluminum are solid residues in oxide form; conducting a liquid-solid separation and removing the solids; and recovering the nickel, cobalt, and manganese from the liquid-metal concentrate. The leachate is recovered and the nitric acid from the leachate is recycled.

Abstract: A system and method for recovering a metal value from a metal-bearing ore material are provided. A metal-bearing ore can be mixed with certain substances and to form an agglomerated ore. In an intermediate state, between agglomeration and heap formation, bacteria can be added to the metal-bearing ore material to produce an augmented ore. The augmented ore can then be formed into a heap.

Abstract: An outstandingly low environmental impact wet process recovers the lead content of an electrode slime and/or of lead minerals in the valuable form of high purity lead oxide or compound convertible to highly pure lead oxide by heat treatment in oven at relatively low temperature, perfectly suited for making active electrode pastes of new batteries or other uses.

Abstract: A heap is constructed with hypogenic copper sulfide bearing ore to include exposed sulfide mineral particles at least 25 weight % of which are hypogenic copper sulfides. The concentration of the exposed sulfide mineral particles is such that the heap includes at least 10 Kg of exposed sulfide sulfur per tonne of solids in the heap. At least 50% of the total copper in the heap is in the form of hypogenic copper sulfides. A substantial portion of the heap is heated to at least 50° C. The heap is inoculated with a thermophilic microorganism, and bioleaching is carried out so that sufficient sulfide mineral particles in the heap are biooxidized to oxidize at least 10 Kg of sulfide sulfur per tonne of solids in the heap and to cause the dissolution of at least 50% of the copper in the heap in a relatively short period of time.

Abstract: The present invention is directed to a precious metal recovery process in which basic ferric sulphates and/or jarosites are controlled by a number of mechanisms, including control of the oxidation reaction conditions in the first autoclave compartment, hot curing of the autoclave discharge slurry, and/or contacting of the autoclave feed slurry with the hot cured discharge liquid.

Abstract: The invention provides a recycling step in an oxidative pressure leaching process for recovery of metals using halide ions, in which a portion of the leached solids are recycled back to the feed to the autoclave, to allow two or more passes through the high temperature leaching step.

Abstract: An object of the present invention is to provide a method of efficiently leaching copper from a copper sulfide ore containing chalcopyrite or enargite as a main constituent under versatile conditions for actual operation. A method of leaching copper from a copper sulfide ore, characterized by comprising using, as a leaching solution, a sulfuric acid solution containing iodide ions and ferric (III) ions in an excessive amount relative to the iodide ions and leaching copper from a copper sulfide ore; or a method of leaching copper from a copper sulfide ore, characterized by comprising leaching copper from a copper sulfide ore with the use of a leaching solution further containing water-soluble ligands such as chloride ions that can stabilize ferric (III) ions in addition to the above components, is provided.

Abstract: The hydrometallurgical process for a nickel oxide ore comprising a step (1) for obtaining an aqueous solution of crude nickel sulfate by High Pressure Acid Leach of a nickel oxide ore; a step (2) for obtaining a zinc free final solution formed; a step (3) for obtaining a waste solution; and a step (4) for scrubbing a hydrogen sulfide gas in exhaust gas, wherein utilization efficiency of hydrogen sulfide gas is enhanced while maintaining nickel recovery rate. It is characterized in that at least one kind of the following operations (a) to (d) is adopted. (a) to adjust total volume (m3) of the sulfurization reactor (B) in the above step (3), at a ratio of 0.2 to 0.

Abstract: Nickel entrained in the sulphide mineral pyrrhotite is engineered to dissolve in leaching acid in a two step procedure. First, a slurry of the mineral and the acid is activated by oxidation. This is done in a time T1 by electrolysis; or alternatively chemically, by adding e.g an oxidizing acid to the mineral. After activation, the slurry is then kept under anoxic conditions for a time T2. During T2, the sulphide starts to dissolve much more rapidly, and the rapid breakdown of the sulphide enables the nickel to dissolve and thus to be leached out of the mineral. The dissolved nickel is extracted from the leaching acid e.g by electro-winning.

Abstract: A method for recovering metal values from refractory sulfide ores is provided. The method includes the steps of separating clays and fines from 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 metal values contained therein.

Abstract: The invention relates to a method of recovering molybdenum from a molybdenum bearing sulfide material. The material is contacted with a leaching solution in the presence of iron compounds and mesophilic or thermophilic iron oxidizing microorganisms and subsequently, a leaching process is performed by controlling the molar ratio of dissolved ferric iron to dissolved molybdenum. Preferably, a high amount and molar excess of dissolved iron is used. The presence of high concentrations of ferric iron in bioleach solutions allows iron-oxidizing microorganisms to grow and oxidize iron and bioleach molybdenite at dissolved Mo concentrations as high as 4.4 g/L. Organic metabolites were not required for protecting cells from Mo toxicity. Maximum dissolution rates depend on reactor configuration, with agglomerated material simulating heap leaching of almost 1% Mo/day, but up to 10.2% Mo/day in suspension/stirred reactor configurations, with rate highly dependent on temperature within the range of 25° C. to 40° C.

Abstract: The disclosed invention provides a process for enhanced recovery of one or more metal values from heap and/or dump leaching of ores containing the metal values, the process comprising: (a) providing a high grade leach solution obtained by heap or dump leaching of fresh high grade ore containing a first metal value; (b) subjecting the high grade leach solution to a first solvent extraction of the first metal value and applying the resulting first aqueous raffinate to leach fresh high grade ore; (c) providing a low grade leach solution obtained by heap or dump leaching of partially leached ore or fresh low grade ore of the first metal value; and (d) subjecting the low grade leach solution to a second solvent extraction of the first metal value, separate from the first solvent extraction of the first metal value, and applying the resulting separate, second aqueous to leach partially leached ore or fresh low grade ore, wherein the first and second aqueous raffinates are not intermixed prior to being applied t

Abstract: The efficiency of an exothermic autoclave leach process is increased by increasing the retention time of the solids fraction in the feed slurry over that of the liquid fraction. This is achieved by flashing the contents of the first oxidative autoclave compartment to a flash vessel, with the underflow therefrom passing to a thickener and the underflow from the thickener being fed to the autoclave feed tank or any tank upstream of the feed tank. Exothermic heat generated in the first compartment of the autoclave is abstracted in the flashing process. Additionally portions of the overflow from the thickener are returned to the feed tank and fed to the autoclave discharge tank.

Abstract: A method is provided for recovering a catalytic element from a fuel cell membrane electrode assembly. The method includes grinding the membrane electrode assembly into a powder, extracting the catalytic element by forming a slurry comprising the powder and an acid leachate adapted to dissolve the catalytic element into a soluble salt, and separating the slurry into a depleted powder and a supernatant containing the catalytic element salt. The depleted powder is washed to remove any catalytic element salt retained within pores in the depleted powder and the catalytic element is purified from the salt.

Abstract: The present invention relates to an improved method for the recovery of metal values, in particular copper and gold, from a metal value-bearing material containing arsenic and/or antimony and a source of sulphate ions, by means of a high temperature pressure oxidation process followed by cyanidation of the resultant high temperature pressure oxidation residue.

Abstract: The invention relates to a method for the leaching of oxidized ores and in particular zinc ores. The ore, wherein the valuable metals are at least partially in silicate form, are routed to an acidic leaching stage in conditions where the silicate decomposes and the valuable metal ion comes into the solution. During leaching the silicate ion first dissolves, but simultaneously decomposes and is precipitated as silica.

Abstract: A process for recovering rare earth elements from a composite ore containing rare earth elements that includes a monazite group mineral and an apatite mineral, includes pre-leaching the composite ore with an acid so as to substantially dissolve the apatite mineral into the leach liquor and precipitating rare earth elements from the pre-leach liquor. The residue of the pre-leaching step is subjected to an acid bake treatment, followed by a water leach, to produce a water leach liquor rich in rare earth elements. Impurities including thorium and iron are separated from the water leach liquor by introducing a neutralizing additive to the water leach liquor rich in rare earth elements, and rare earth elements are precipitated from the post-neutralization liquor.

Abstract: An improved process and composition for the extraction of metal from a metal-laden ore, soil or rock is provided. A liquid, three-component aqueous lixiviant comprises water, an alkali metal salt and a low pH acidic composition. A four-component aqueous lixiviant comprises water, a low pH acidic composition, an alkali metal salt and an acid having a pH value less than 2. Both lixiviant compositions are efficient for extracting metal into a pregnant liquid solution. The pregnant solution is treated by known conventional means, such as filtration, centrifuging or electrolysis to remove the extracted metals. The three-component and four-component aqueous lixiviants of the present invention are non-toxic, meaning, not an irritant or deleterious to humans or the environment and perform, as well as, or better than known toxic cyanide lixiviants.

Abstract: The present invention concerns a process for the instantaneous control of the precipitation of nickel and cobalt present in a leach liquor by adjustment of the pH-value. Said leach liquor is obtained by pressurized acidic leaching of laterile ores and additionally contains aluminium, ferric and ferrous iron and chromium among others. The process comprises the following steps: precipitation of aluminium, ferric and ferrous iron, chromium etc. by increasing the pH- value by adding a suitable reagent such as lime and/or limestone, following precipitation of nickel and cobalt by further increasing the pH-value of the liquor, finally separating the precipitate from the low-content nickel and cobalt solution. The nickel and cobalt precipitate can be used for further refinement. In order to keep the process conditions constant, the steps of increasing the pH-value are controlled simultaneously.

Abstract: The copper sulfide ore is leached in the halide bath without using a special oxidant but with the use of only air. The copper and gold in the copper sulfide ore can be leached at high leaching ratio. The treating steps are as follows. (1) Copper leaching process (CL). The raw material is charged into the first acidic aqueous solution, which contains cupric chloride, ferric chloride, 7 g/L of hydrochloric acid, and sodium chloride. The post-leach liquor contains copper in cuprous state ions and copper in cupric state ions. (2) Solid-Liquid separation step. The resultant solid and liquid of CL step are separated. (3) Air oxidation step (OX). Air is blown into the post solid-liquid separation liquor. The copper in cuprous state ions are oxidized to the copper in cupric state ions. The iron leached in the step (1) is oxidized. Simultaneously, the impurities leached in the step (2) are precipitated. (4) Copper extracting step (CEX).

Abstract: A method of obtaining copper from sulfide ore including copper (hereinafter referred to as feedstock) includes: providing feedstock into acid solution, the acid solution including chloride and bromide of one of alkali metal and alkali earth metal, and one of chloride of copper and iron and bromide of copper and iron; leaching monovalent copper and divalent copper from the feedstock with use of oxidizing power of at least one of iron ion and copper ion in the acid solution, with air being blown into the acid solution under an atmospheric pressure at a temperature less than a boiling point of the acid solution; solid-liquid separating the acid solution after the leaching; blowing air into the solution after the solid-liquid separation; oxidizing copper in the solution; coprecipitating iron and impurity that are leached into the acid solution from the feedstock; extracting copper from the solution after the oxidizing from which deposition including the coprecipitate is separated; obtaining the extracted copper i

Abstract: An object of the present invention is to provide a method of recovering copper from primary copper sulfide ores containing chalcopyrite as a main constituent under versatile conditions for real operation in all efficient and cost-effective manner. A method of leaching copper sulfide ores, wherein the growth of microorganisms present on ore surfaces and in a leaching solution is inhibited and the pH of the leaching solution is adjusted to 1.5 or less upon leaching of copper from copper sulfide ores containing chalcopyrite, is provided.

Abstract: The invention relates to a process for the pre-treatment of feed to a non-stirred surface heap leach bioreactor by applying in sequence first and second pre-treatment solutions to a feed to a non-stirred surface heap leach bioreactor, in which the first solution has an iron content greater than 5 g/l and pH below 2, and the second solution contains a substantially higher microbial population. The invention further relates to methods of adapting a microbial population for use in a non-stirred surface heap leach bioreactor.

Abstract: A process for the leaching of metals from highly oxidized laterite ores. The ore is admixed with an acidic aqueous medium, preferably a solution of sulfuric acid and the resulting mixture is treated with a sulfur reducing agent so as to reduce mineral species containing cobalt, nickel or manganese. The sulfur reducing agent may be an aqueous solution of sulfur dioxide or more preferably the sulfur dioxide is generated in situ by the reduction of alkali metal sulfite salt. The process is conducted at ambient temperature and pressure with the reduced mineral species being dissolved and subsequently recovered.

Abstract: Small magnetic particles are introduced into a solution which is subjected to a bioleaching process. The particles are coated with a substance which has a selective affinity for, and which interacts with, a metal in the solution. The particles are taken from the solution and the metal is recovered from the particles.