Abstract: The invention discloses a method of controlling a heap leach process through controlling an irrigation rate of a heap as a function of at least one of an aeration rate of the heap, a determination of advection at least at one predetermined point in the heap, and a determination of temperature at least at one predetermined point in the heap. Also disclosed is for the aeration to be forced and for the method to include the step of controlling the aeration rate as 10 a function of a determination of the oxidation rate of material within the heap. The invention also extends to a method for the introduction of microorganisms into the heap of material, a method for increasing the temperature of heap of material for heap leaching, a method of determining an optimum heap configuration for a bio-assisted heap leach process of an ore heap, and a method of enriching the environment of microorganisms embedded in a heap of material for bio-assisted heap leaching.

Abstract: A method is described of treating aluminium-metal alloys with organic or inorganic bases by exposing them to an aqueous solution of the base, removing the aqueous base and washing the treated alloy material, the leaching process being monitored, during the time of exposure to the base, on the basis of the potential which is established at a measuring electrode as a result of the treated aluminium-metal alloy and the hydrogen which may be formed during the reaction.

Abstract: A process for production of titanium concentrate with low contents of radionuclide elements from anatase mechanical concentrates. The process involves calcination in air and reduction with hydrogen or any other reducing gas, both in fluidized bed reactor or rotary kiln, low-intensity magnetic separation of the reduced product, high-intensity magnetic separation of the non-magnetic fraction resulting from the low-intensity magnetic separation, hydrochloric acid leaching of the product of high-intensity magnetic separation, filtering and dewatering of the leached product, high temperature oxidation of the dewatered material, cooling of the oxidized ore, hydrochloric acid leaching of the oxidation product in the presence of sodium fluoride, filtration and drying of the product of the second leaching and high intensity magnetic separation, the non-magnetic fraction of this final magnetic separation becoming the end product.

Abstract: A heap bioleaching process wherein carbon, in the form of a carbonate, carbon dioxide or organic carbon, is added to the heap when the temperature in the heap is in the range of 45° C. to 60° C. to increase microbial activity and thereby raise the heap temperature to about 60° C.

Abstract: A process is described for the recovery of nickel and cobalt from a nickeliferous laterite ore including the steps of: providing a nickeliferous laterite ore and separating that ore into its low magnesium limonite fraction and high magnesium saprolite fraction; treating the limonite fraction in acid solution in a primary high pressure leach step to produce a primary leach slurry; adding the saprolite fraction to the primary leach slurry to initiate precipitation of iron as goethite and/or hematite, while simultaneously releasing further acid from the iron precipitation, to effect a secondary atmospheric leach step, producing a secondary leach slurry; wherein all water used to prepare the ore slurries and/or acid solutions has an ionic composition that substantially avoids jarosite formation.

Abstract: A heap leaching method to recover copper from a primary copper sulphide mineral wherein the mineral is leached in an acidic chloride/sulphate solution in the presence of oxygen with the surface potential of the mineral below 600 mV (vs. SHE) to cause dissolution of the copper sulphide.

Abstract: The present invention relates to the use of monodisperse, macroporous chelating resins in the recovery of metals in hydrometallurgical processes, in particular in resin-in-pulp processes.

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: A process for recovering nickel from a solid feed material containing nickel in the form of millerite is disclosed. The process includes treating a slurry of the solid feed material and a process solution so that all or at least part of the nickel in the millerite forms an acid leachable solid form. The process also includes pressure acid leaching the treated slurry and leaching nickel in solids in the slurry into solution. Finally, the process includes recovering nickel from solution.

Abstract: A sample preparation method for characterization of nanoparticles embedded in the supports of heterogeneous catalysts, with improved particle dispersion, is introduced. The supported catalyst is first ground or milled into fine powder. Then, the powder is mixed into an organic solvent, and an etchant is added to the solvent to digest the supports and release metallic nanoparticles. The resulting solution is then placed in an ultrasonic bath where ultrasonic waves are generated and applied to the solution. The ultrasonic waves suppress agglomeration of the particles and also break up those particle clusters resulting from agglomeration during the prior steps. Subsequently, a sample is extracted from the solution and prepared for analysis.

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 invention relates to a method for processing concentrates, particularly concentrates produced from copper sulfide-based ores. According to the method, the concentrate (4) to be processed, obtained from ore concentration, is divided into two parts, to a concentrate (7) mainly containing poorly soluble components, and to a concentrate (8) mainly containing well soluble components. The concentrate (8) containing well soluble components is conducted to a leaching step (9), and the solution (13) obtained from said leaching step is conducted to at least one conversion step (11, 16), and to the conversion step (11) that is located first in the flowing direction, there is fed the concentrate (7) containing poorly soluble components.

Abstract: The invention relates to a method whereby copper is recovered from a copper sulphide ore containing pyrite. According to the method the ore is ground and leached into a solution containing sulfuric acid in atmospheric conditions by means of trivalent copper. As the copper sulphide leaches out, the trivalent iron is reduced to divalent and is oxidized back to trivalent by means of oxygen during leaching. Leaching is carried out in a closed reactor, where the undissolved gas rising from the solution in the supper section of the reactor is circulated back into the suspension of solution, solids and gas. leaching is performed in the presence of both divalent and trivalent iron and preferably with the dissolved copper acting as a catalyst to promote leaching. The conditions are adjusted to be such that the pyrite of the ore essentially does not dissolve.

Abstract: Aqueous leachant compositions and processes for using the same comprising: (a) providing a metal-containing compound; and (b) subjecting the metal-containing compound to an acid digestion comprising contacting the metal-containing compound with an aqueous leachant; wherein the aqueous leachant comprises a mixture selected from the group consisting of: (i) sulfuric acid and one or more alkanesulfonic acids having alkane moieties selected from the group consisting of propyl, ethyl and methyl groups, at a weight ratio of alkanesulfonic acid to sulfuric acid of 1:1000 to 1:1; (ii) sulfuric acid and one or more salts of alkanesulfonic acids having alkane moieties selected from the group consisting of propyl, ethyl and methyl groups, at a weight ratio of salt of alkanesulfonic acid to sulfuric acid of 1:9 to 1:99.

Abstract: A method for suppressing mercury dissolution during pressure oxidation of precious metal-containing materials in the presence of halogens and halides is provided. Pressure oxidation is performed under controlled oxidative conditions to maintain the mercury predominantly in the solid residue.

Abstract: A hydrometallurgical resin-in-leach (RIL) process for directly recovering nickel and/or cobalt. Simultaneous pulp leaching by adding an acid or base, dissolves the metals of interest with adsorption of the metals rendered soluble in on ionic exchange resin. Following elution of the changed resin, purification of nickel and cobalt present in the eluate can be recovered by conventional methods, such as precipitation, extraction by solvents and membranes. The regenerated resin is recirculated for further use.

Abstract: The present invention refers to a hydro-metallurgical process using resin-in-neutralized-solution in heap leaching effluent. More specifically, the process is applicable to lateritic ore, nickel oxidate, cobalt oxidate or a mixture containing metals of interest—nickel, cobalt and other secondary metals, wherein ore is leached by adding an acid or a base with possible pH adjustment, aided by acid or base with neutralization of heap leaching effluent, by adding lime, limestone, soda or ammonia in the temperature of 70° to 95° C.

Abstract: The present invention is related to a hydrometallurgical process to produce nickel as hydroxide, oxide or cathode and produce cobalt preferably as sulfides. The present invention is particularly adequate to process eluate containing nickel and cobalt. Eluates are solutions obtained from elution of ionic exchange resins, loaded (charged) in the RIP (resin-in-pulp) process of ionic exchange, to recover nickel and cobalt from effluent pulps in acid leaching. Following nickel and cobalt recovery in a RIP circuit, they are separated from each other via a continuous ionic exchange process, after which the nickel eluate is formed to produce nickel as nickel oxide by a pyrohydrolysis process.

Abstract: A method for optimizing a bioleaching process, at least in respect of heat generation and primary copper sulphide leaching, by actively monitoring and controlling inorganic and organic compounds in a raffinate solution, produced in the process, to levels below that which could be inhibitory to microbial activity of bioleaching strains used in the process.

Abstract: The invention relates to a method for smelting sulfidic copper concentrates, in which method copper sulfide bearing material is smelted in a smelting furnace (1) for creating blister copper and slag. According to the method, at least part (3) of the feed of the smelting furnace (1) is copper sulfide bearing (3) material obtained by means of sulfide bearing material (2) that is fed into the hydrometallurgic further processing (12,19) of slag (11) created in the smelting process.

Abstract: Precious metals such as gold can be extracted from a refractory ore using a conventional cyanide leaching step and with reduced cyanide consumption by pre-treating the ore prior to cyanide leaching. The refractory ore is pretreated by fine grinding and an initial leaching step which uses inexpensive limestone and lime to maintain the initial leach relatively alkaline. Oxygen is added to the initial leaching step and the conditions are carefully controlled to only partially oxidize the ground ore to between 9-15%. The initial leaching step can be carried out at temperatures of less than 100 degrees C. and at atmospheric pressures. The pre-treated ore is then leached by a conventional cyanide leaching step to recover the precious metal and cyanide consumption can be reduced by more than two thirds.

Abstract: A method for the recovery of metal values from a metal value-bearing material containing arsenic and/or antimony and a source of sulphate ions such as sulphide ore or concentrate is disclosed.

Abstract: A process for the recovery of zinc metal from a zinc mineral includes the steps of leaching the zinc mineral in a solution including a halide species formed from two or more different halides, to leach the zinc into the solution. The zinc-bearing solution is then electrolyzed to yield zinc metal and to generate the halide species. The electrolyzed solution including the halide species is then returned to the leaching step. A portion of the electrolyzed solution can be removed as a bleed stream from a cathode compartment of an electrolytic cell of the electrolysis process and processed to remove manganese as manganese dioxide precipitate by adding thereto limestone, and the halide species from an anode compartment of the electrolysis process. In this regard, the pH and Eh of the solution can regulated in a manner that favors the formation of the manganese dioxide precipitate over the formation of a precipitate of zinc.

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: A method of extracting zinc from a sulphidic ore is provided which comprises bioleaching the ore in a heap with acidophilic microorganisms to produce a pregnant leach solution which is recovered from the bottom of the heap. An integrated process which comprises subjecting the pregnant leach solution to neutralization and solvent extraction to produce a concentrated zinc solution is also provided. Zinc may be recovered from the concentrated solution by means of electrowinning, either in the absence or presence of manganese. Alternatively zinc may be recovered in the form of a zinc compound.

Abstract: A process for efficient separation/recovery of copper involving selective extraction of the copper ion with the aid of an organic extractant from an aqueous chloride solution containing copper and one or more concomitant elements, discharged from an extractive metallurgy of non-ferrous metals or the like, and subsequent stripping. The process of solvent extraction of copper which treats an aqueous chloride solution containing copper and one or more concomitant elements to separate/recover copper, comprising the first step for selective extraction of copper from the aqueous chloride solution by mixing the solution with an extractant of organic solvent composed of tributyl phosphate as the major component after adjusting the solution at an oxidation-reduction potential of 0 to 350 mV (based on an Ag/AgCl electrode), and the second step for stripping of copper by mixing the extractant in which copper is stripped with an aqueous solution.

Abstract: Sulphidic zinc concentrate usually also includes small amounts of rare metals such as indium and gallium. If the content of these metals in the raw material is sufficiently high, their recovery may be economically worthwhile. In the method according to the invention the recovery of indium and other desirable rare metals takes place in a zinc leaching process, in which at least part of the sulphidic concentrate is leached directly without roasting.

Abstract: An atmospheric leaching process in the recovery of nickel and cobalt from a lateritic ore, the lateritic ore including a low magnesium ore fraction and a high magnesium ore fraction, the process including the steps of: (a) forming an aqueous pulp of the lateritic ore, (b) leaching the aqueous pulp with a concentrated mineral acid at atmospheric pressure to produce a slutty containing a pregnant leach liquor and a leach residue, (c) treating the pregnant leach liquor either separately or as part of the slurry to recover dissolved nickel and cobalt therefrom, leaving a magnesium barren solution, (d) treating the magnesium containing solution to recover a magnesium containing salt therefrom.

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.

Abstract: The present invention relates generally to a process for recovering copper and other metal values from metal-containing materials using controlled, super-fine grinding and medium temperature pressure leaching. Processes embodying aspects of the present invention may be beneficial for recovering a variety of metals such as copper, gold, silver, nickel, cobalt, molybdenum, rhenium, zinc, uranium, and platinum group metals, from metal-bearing materials, and find particular utility in connection with the extraction of copper from copper sulfide ores and concentrates.

Abstract: The invention relates to a method for obtaining metals from a cobalt and/or nickel arsenic sulfide ore or ore concentrate and/or a cobalt and/or nickel sulfide ore or ore concentrate, according to which the cobalt and/or nickel arsenic sulfide ore or ore concentrate and/or the cobalt and/or nickel sulfide ore or ore concentrate is reacted with sulfur or sulfur arsenic compounds to a reaction product, and dissolving and removing soluble metals and rare-earth metals.

Abstract: A composition for cyanide leaching which comprises at least one nonionic surfactant and a process for extracting metals using the abovementioned composition are described.

Abstract: A heap bioleaching process wherein carbon, in the form of a carbonate, carbon dioxide or organic carbon, is added to the heap when the temperature in the heap is in the range of 45° C. to 60° C. to increase microbial activity and thereby raise the heap temperature to about 60° C.

Abstract: A process of bioleaching a sulphide mineral slurry in a reactor which is controlled by varying the rate of supply of sparging gas to the reactor, and the energy supplied to a motor-driven agitator in the reactor, in response to the measured or inferred oxygen demand of the slurry.

Abstract: Improved methods for treating metallurgical compositions involve reacting a metallurgical composition with an aqueous nitric acid solution. The reaction is performed at a pressure of at least about 220 psig and at a temperature of at least 100° C. The metallurgical composition comprises iron and one or more non-ferrous metals. The reaction dissolves the majority of the non-ferrous metal compositions into the solution which is in contact with solid ferric oxide. The reaction can be repeated on the isolated solids to increase the purity of ferric oxide in the solids. Zinc can be removed from the mixed metal solutions obtained from furnace dust by a variety of separation techniques.

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 refractory metal recovery method includes applying a coolant to a wheel grinding operation at a total rate exceeding a total rate at which the coolant evaporates and distributing the coolant across an interface with the abrasive wheel sufficient to apply the coolant at local rates exceeding local rates at which the coolant evaporates. The method produces refractory metal swarf and decreases oxidation of the swarf compared to dry grinding, allowing collection of the swarf. The abrasive grit may have a size of from about 16 to about 24 mesh and the coolant may contain a nitrite.

Abstract: The present invention relates generally to a process for recovering copper and other metal values from metal-containing materials using controlled, super-fine grinding and medium temperature pressure leaching. Processes embodying aspects of the present invention may be beneficial for recovering a variety of metals such as copper, gold, silver, nickel, cobalt, molybdenum, rhenium, zinc, uranium, and platinum group metals, from metal-bearing materials, and find particular utility in connection with the extraction of copper from copper sulfide ores and concentrates.

Abstract: A method for passivating sulfidic iron-containing rock comprising: contacting sulfidic iron-containing rock with a magnesium-containing substance, a manganese-containing substance, and a calcium-containing substance; and adjusting the pH of the system to below about 11, is provided. The method can be used to prevent acid rock drainage of metal-bearing rocks or to produce a pretreated ore or rock which can be contacted with a lixiviating agent to extract metals from the pretreated ore or rock.

Abstract: The invention relates to the removal of bivalent copper from copper chloride solution in connection with the hydrometallurgical production of copper. In the copper production process, a copper-bearing raw material is leached with a chloride-bearing solution. The copper chloride solution formed in the leaching, which contains both mono- and bivalent copper, undergoes bivalent copper removal at least in part by precipitation, and the copper(I) chloride solution is conduced to further treatment. Precipitation of the bivalent copper occurs as alkaline copper chloride precipitation. The alkaline copper (II) chloride formed is leached as copper(II) chloride either separately or in connection with raw material leaching, and is used in copper raw material leaching.

Abstract: A circuit configuration for a metal solvent extraction plant comprising: A) an extraction section for extracting metal ions from an aqueous leach solution containing the metal ions with an organic solvent solution containing at least one metal extraction reagent, wherein the extraction section consists of three countercurrent extraction stages; and B) a stripping section consisting of one stripping stage for stripping the metal ions from the metal extraction reagent.

Abstract: An interlaced series parallel configuration for the extraction of metal values from an metal value containing aqueous is a special series parallel configuration wherein the stripped organic is first contacted in a second extraction stage with the partially copper depleted aqueous stream exiting from a first extraction stage. This partially loaded organic then advances to a parallel extraction stage where it is contacted with a fresh volume of PLS and extracts additional copper. The organic then advances to the first extraction stage where it contacts a second stream of PLS. This approach results in an overall higher recovery of copper than in the conventional modified series parallel configuration. An increase of 4% overall recovery of copper is achieved relative to that realized with the conventional series parallel configuration.

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: Improved methods for the extraction or dissolution of metals, metalloids or their oxides, especially lanthanides, actinides, uranium or their oxides, into supercritical solvents containing an extractant are disclosed. The disclosed embodiments specifically include enhancing the extraction or dissolution efficiency with ultrasound. The present methods allow the direct, efficient dissolution of UO2 or other uranium oxides without generating any waste stream or by-products.

Abstract: The present invention relates generally to a process for the production of sulfuric acid and liberation of precious metal values from materials containing sulfur through pressure leaching operations. In accordance with various aspects of the present invention, the sulfur-bearing materials may comprise residues from pressure leaching operations, such as those carried out at medium temperatures. The process of the present invention can be advantageously used to convert such sulfur-bearing materials to sulfuric acid by means of pressure leaching. The sulfuric acid so produced can be used beneficially in other mineral processing operations, for example those at the site where it is produced. Metals, such as precious metals, that are contained within the sulfur-bearing materials advantageously may be recovered from processing products by established precious metals recovery technology.

Abstract: A method to dissolve at least one metal from jarosite or other iron hydroxyl sulphate containing-material which includes the steps of subjecting the material to alkaline treatment in a brine solution to facilitate jarosite decomposition, and acidification of the brine slurry to solubilise the liberated metal.

Abstract: The process of the present invention recovers platinum group metal(s), such as platinum and palladium, from PGM-containing materials containing base metals, such as copper and nickel. The process controls sulfur levels by using solvent extraction 306 to remove acid in the nickel recovery circuit. The acid product 326 can then be neutralized and/or recycled as desired.

Abstract: A method of recovering metal and/or oxide thereof from a slurry is described. The method involves magnetically separating at least a portion of any magnetic impurities from the slurry and then leaching or dissolving at least a portion of any remaining magnetic impurities in a slurry. At least one chelating agent can then be added to the slurry and the solids can be recovered from the slurry by various separation techniques. The methods of the present invention are particularly useful in the recovery of tantalum and/or oxide thereof especially tantalum and/or oxide thereof having a very fine size.

Abstract: This invention relates to a method where sulfidic iron-bearing copper concentrate is leached on the countercurrent principle, in a chloride environment. The leaching takes place with the aid of bivalent copper and an oxygen-bearing gas as a multi-stage continuous process, under normal pressure, at a temperature, which as highest corresponds to the boiling point of the solution. Part of the insoluble solid matter is returned, counter to the main flow of solid matter, to one of the previous leaching stages or reactors where, as a result of the extended leaching time, the leach waste iron is recovered mostly as hematite.

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.