Abstract: Process for the control of dust on ore handling points comprising applying to the ore an aqueous solution of an alkyl polyglucoside having an average of from 8 to 12 carbon atoms and a degree of polymerization of from 1.4 to 1.6.

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: Process for the control of dust on ore handling points comprising applying to the ore an aqueous solution of an alkyl polyglucoside having an average of from 8 to 12 carbon atoms and a degree of polymerization of from 1.4 to 1.6.

Abstract: A hydrometallurgical process for the recovery of nickel and cobalt values from a sulfidic flotation concentrate. The process involves forming a slurry of the sulfidic flotation concentrate in an acid solution, and subjecting the slurried flotation concentrate to a chlorine leach at atmospheric pressure followed by an oxidative pressure leach. After liquid-solids separation and purification of the concentrate resulting in the removal of copper and cobalt, the nickel-containing solution is directly treated by electrowinning to recover nickel cathode therefrom.

Abstract: The invention is concerned with techniques and apparatus suitable for extraction of at least one valuable metal such as one or more of: gold, platinum, silver, cobalt, nickel, molybdenum, and manganese from a starting material which, by way of example, could be freshly mined mixed ore containing both oxidic and refractory (sulphide) ores.

Abstract: Methods for enhancing the leaching of copper from copper bearing ores with an aqueous sulfuric acid leach solution are disclosed wherein an antifoam formulation stable at a solution pH of about 1 to 2 is added. A preferred antifoam formulation comprises a glycol ester and an alkyl phenol ethoxylate in a paraffinic oil solvent added to the aqueous sulfuric acid leach 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 process for leaching an ore that contains nickel and magnesium includes mixing a microorganism that is capable of producing an organic acid, a nutrient, and an ore that contains nickel and magnesium for a period of time to dissolve the nickel and form a solution containing a nickel salt and a magnesium salt, separating the nickel from the magnesium in the salt solution.

Abstract: An improved process of hydrometallurgical treatment of laterite ores predominantly of the limonitic type for the recovery of nickel and cobalt using sulphuric acid. In order to obtain high extractions of these metals while treating these ores in their humid state, in reaction times of up to 60 minutes, temperatures of up to 270° C. and corresponding pressures of up to 800 psia are used. In the present invention, a significant portion of the “mother liquor” emanating from the pressure leaching reaction is recycled to the feed preparation stage thereby substituting for all or a major proportion of the water that must be added. Concomitantly with the major savings in water requirements, a significant reduction in new sulphuric acid requirements is effected along with a corresponding saving in limestone and lime required for subsequent neutralizations. The amount of process water released to the environment is significantly reduced or eliminated.

Abstract: Invention relates to a method for the removal of sulfur from the leaching cycle of nickel processes such as leaching of nickel matte. According to the method, anolyte generated in nickel electrowinning is neutralized with the aid of a calcium-based neutralizing agents, wherein sulfur is removed from the leaching cycle as gypsum.

Abstract: Process for improving recovery of copper and reducing raw material costs, from a copper-containing source by SX-EW. The process comprises the steps of mixing an acidic copper-containing PLS obtained by leaching a copper-containing source with an acidic leachant, usually sulfuric acid, with an aqueous acidic cupric chloride solution spent printed wire board etchant, to produce an acidic cupric chloride/copper sulfate-containing mixture. This mixture is subjected to SX-EW to recover the copper as copper cathode.

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: The process uses hydrochloric acid solutions to extract zinc from electric arc furnace dusts containing zinc oxide and zinc ferrite. To selectively leach zinc and minimize iron dissolution by precipitating as FeO.OH and Fe2O3, hot acid leaching with the aqueous solution containing 37 g/l-74 g/l HCl and 104 g/l-270 g/l ZnCl2 is used. New dust is introduced to remove iron from the filtrate of the hot acid leaching. The zinc chloride solutions purified by activated carbon and metallic zinc powder is electrolysed in electrowinning cells which had cation exchange membrane to produce high purity zinc metal and to regenerate hydrochloric acid. Electrolysing an aqueous solution of zinc chloride with Zn concentration of 50-130 g/litre below 40° C. in a cell divided by cation exchange membrane, whereby coherent zinc is yielded at the cathode with high current efficiency of exceeding 90%. HCl is directly regenerated with a very small loss below 2% and low energy consumption below 5.

Abstract: A process for treating zinc mine tailings wherein a series of wave tables and cone separators are utilized to remove various components from the zinc mine tailings, such as carbon, zinc, lead, copper and precious metals. The recovered carbon is then transferred to a cogeneration plant where it is utilized as fuel.

Abstract: A process is provided for heap leaching ore to recover nickel. The process is particularly effective for ores that have a tangible clay component (i.e., greater than about 10% by weight). The process includes sizing the ore (where necessary), forming pellets by contacting ore with a lixiviant and agglomerating. The pellets are formed into a heap and leached with sulfuric acid to extract the metal values, including nickel. The leachate may be subjected to a nickel recovery operation without the need for intermediate neutralization.

Abstract: A process for recovering a base metal from a material, the base metal being selected from cobalt, copper, nickel and zinc, the process comprising the steps of reacting the host material with a ferric ion species in a leach solution, at conditions sufficient to cause at least a portion of the base metal to be oxidized by the ferric ion species, thereby causing the ferric ion species to be converted to a ferrous ion species, and oxidizing the ferrous ion species with an oxidation mixture of SO2 and oxygen to form the ferric ion species for subsequent reaction with the material.

Abstract: The present invention concerns a composition and method for separating heavy metals from contaminated substrates with compositions containing active agent selected from the group consisting of [S,S]-ethylene diamine disuccinic acid and [S,S]-di-imine butane dioic acid.

Abstract: A method for inhibiting crud formation and organic in aqueous solvent and aqueous in organic solvent entrainment in the solvent extraction of copper from an aqueous sulfuric acid pregnant leach solution is disclosed. The method comprises adding an antifoam formulation stable at a solution pH of about 1 to 2 is added. A preferred antifoam formulation comprises a glycol ester and an alkyl phenol ethoxylate in a paraffinic oil solvent added to the acid solution.

Abstract: A process for the recovery of copper and nickel from a copper and nickel sulphide concentrate in slurry form. The slurry is subjected to a biological oxidation turning the copper sulphide to soluble copper sulphate and the nickel to nickel sulphate. The liquid containing the sulphates is separated from the slurry and treated with a solvent extraction reagent so that copper ions are exchanged by the reagent for hydrogen ions to produce a raffinate which is high in sulphuric acid and low in copper sulphate. The solvent extraction reagent is then stripped from the raffinate with a sulphuric acid solution. Copper is electrically harvested from the sulphuric acid solution and a portion of the copper depleted raffinate is returned to form a slurry with additional ore for subsequent biological oxidation. Nickel is recovered from the remaining portion of the raffinate.

Abstract: A system for recovery of metals from solutions containing dissolved metals. The system includes an apparatus and method for placing supercritical carbon dioxide that contains an extractant in contact with the solution and agitating the two resulting phases. Once the metals are extracted by the extractant, they can be removed from the carbon dioxide phase by depressurization or by reduction by exposure to hydrogen. The extractant preferably comprises a metal binding group, a spacer group and a C02-philic group.

Abstract: A method and apparatus for bioprocessing particles wherein particles are entrapped a porous material and have biologically active microorganisms on their surfaces. A liquid (carrying oxygen and/or nutrients for said microorganisms) is passed through the entrapped particles and microorganisms and microorganisms are active to breakdown said particles. After a suitable period of time the particles are removed from the matrix.

Abstract: The invention relates to a method for leaching sulfidic nickel matte and particularly copper rich nickel matte, as well as for leaching said matte together with a metallic copper and/or copper-nickel matte. The leach of nickel matte is carried out as pressure leach in one or several stages by means of copper sulfate.

Abstract: The process of the present invention “jump starts” heap biooxidation of sulfides by incorporating a previously biooxidized material into the heap. The process can be used to recover precious and/or base metals from sulfidic ores and concentrate.

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 .mu.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: Disclosed and claimed is an efficient process for extraction of metals from ores using carbon catalyzed leaching. Specifically exemplified is the extraction of cobalt and nickel from laterite ore.

Abstract: Metals are rendered analyzable, extractable or recoverable from materials, such as complex or refractory ores, by applying shear deformation forces to the materials. The shear deformation forces are generated by methods such as mechanical attrition. Through this process, the precious element-bearing amorphous colloidal silica and other fractions of these ores are reformed and crystallized into what are essentially nanophase materials that show a change of chemical, mechanical, and thermodynamic properties as compared to their original natural state. During or after this transformation, the precious element content of these ores may be reduced to a recoverable state and/or analyzed or detected.

Abstract: A method for reclaiming a metallic material from a article including a non-metallic friable substrate. The method comprising crushing the article into a plurality of pieces. An acidic solution capable of dissolving the metallic material is provided dissolving the metallic material in the acidic material to form an etchant effluent. The etchant effluent is separated from the friable substrate. A precipitation agent, capable of precipitating the metallic material, is added to the etchant effluent to precipitate out the metallic material from the etchant effluent. The metallic material is then recovered.

Abstract: According to the process, a heap preferably having dimensions of at least 2.5 m high and 5 m wide is constructed with chalcopyrite bearing ore. The constructed heap includes exposed sulfide mineral particles at least 25 weight % of which are chalcopyrite. The concentration of the exposed sulfide mineral particles in the heap is such that the heap includes at least 10 Kg of exposed sulfide sulfur per tonne of solids in the heap. Furthermore, at least 50% of the total copper in the heap is in the form of chalcopyrite. A substantial portion of the heap is then heated to a temperature of at least 50.degree. C. The heap is inoculated, with a culture including at least one strain of thermophilic microorganisms capable of bioleaching sulfide minerals at a temperature above 50.degree. C. A process leach solution that includes sulfuric acid and ferric iron is applied to the heap.

Abstract: A method of biooxidizing sulfide minerals in a nonstirred bioreactor is provided. According to the disclosed method, a concentrate of sulfide minerals is coated onto a plurality of substrates, such as coarse ore particles, lava rock, gravel or rock containing a small amount of mineral carbonate as a source of CO.sub.2 for the biooxidizing bacteria. After the sulfide minerals are coated or spread onto the plurality of substrates, a heap is formed with the coated substrates or the coated substrates are placed within a tank. The sulfide minerals on the surface of the plurality of coated substrates are then biooxidized to liberate the metal value of interest. Depending on the particular ore deposit being mined, the sulfide mineral concentrates used in the process may comprise sulfide concentrates from precious metal bearing refractory sulfide ores or they may comprise sulfide concentrates from metal sulfide type ores, such as chalcopyrite, pyrite or sphalorite.

Abstract: A method for improving the heap biooxidation rate of refractory sulfide ore particles that are at least partially biooxidized using a recycled bioleachate off solution is provided.

Abstract: A process for treating ores or rocks is provided. The process comprises (1) combining the ores or rocks with an acid passivating agent to produce a first combination; (2) contacting the first combination with an aqueous solution comprising (a) manganate ions or source thereof and (b) a base whereby a second combination is produced; and (3) maintaining the pH of the second combination at about 11 to about 13.5. The process can also comprise (1) contacting the ores or rocks with the aqueous solution to produce a third combination; (2) contacting the third combination with an acid passivating agent to produce a fourth combination; and (3) maintaining the pH of the fourth combination at about 11 to about 13.5. The process can be used to prevent acid rock drainage of metal-bearing rocks or to produce a pretreated ore or rock which can further be contacted with a lixiviating agent such as, for example, sodium cyanide to extract metals such as, for example, gold and silver from the pretreated ore or rock.

Abstract: A method of biooxidizing sulfide minerals in a nonstirred bioreactor is provided. According to the disclosed method, a concentrate of sulfide minerals is coated onto a substrate, such as coarse ore particles, lava rock, gravel or rock containing mineral carbonate as a source of CO.sub.2 for the biooxidizing bacteria. After the sulfide minerals are coated onto the substrate, a heap is formed with the coated substrates or the coated substrates are placed within a tank. The sulfide minerals are then biooxidized to liberate the metal value of interest. Depending on the particular ore deposit being mined, the sulfide mineral concentrates used in the process may comprise sulfide concentrates from precious metal bearing refractory sulfide ores or they may comprise sulfide concentrates from metal sulfide type ores, such as chalcopyrite, millerite or sphalorite.

Abstract: The subject invention provides a novel process and bioreactor for enhancing the bioleaching of metals from sulfide mineral concentrations.

Abstract: An apparatus for applying a leaching solution to a mass of ore includes a plurality of first tubes which are connected to a supply of leaching solution. Each of the first tubes is fitted with emitters which are positioned at spaced intervals along the length of each first tube. The first tubes are connected with a manifold on their distal ends. A second tube is connected to the manifold. The second tube is fitted with a sprinkler which is positioned to distribute leaching solution over the surface area of the ore mass which is positioned intermediate adjacent emitters.

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 for controlling oxygen in valve metal materials. The method includes deoxidizing a valve metal material, typically tantalum, niobium, or alloys thereof, and leaching the material in an acid leach solution at a temperature lower than room temperature. In one embodiment of the present invention, the acid leach solution is prepared and cooled to a temperature lower than room temperature prior to leaching the deoxidized valve metal material. The method of the present invention has been found to lower both the oxygen and fluoride concentrations in valve metal materials, as the use of reduced acid leach temperatures provide lower oxygen for a given quantity of a leach acid, such as hydrofluoric acid.

Abstract: There is disclosed a process for separating and recovering nickel and copper values from a nickel-copper matte which may contain iron and arsenic. Finely divided nickel-copper matte undergoes one or more steps of sulphuric acid leaching at atmospheric pressure to produce a nickel sulphate solution and an iron and/or arsenic containing copper-rich sulphide residue. The copper-rich sulphide residue is repulped in sulphuric acid solution to selectively redissolve most of the iron and arsenic and the iron and arsenic containing solution is separated from the copper-rich residue. The iron and arsenic are largely precipitated from the leach solution in a pressure hydrolysis step and the iron and arsenic containing precipitate is separated and discarded. The iron and arsenic-depleted solution is recombined with the copper-rich sulphide residue from the acid repulp step and the resulting slurry is treated in a non-oxidizing pressure leach in which nickel arsenic and iron are extracted.

Abstract: Copper and nickel are extracted from their elemental state, complex sulfides, ores, and other materials such as scrap by leaching them with a solution containing halogen salts: bromine/bromide, or iodide/iodine, oxygen and sodium or potassium nitrate. The invented process is particularly effective for chalcopyrite and pentlandite in an autoclave at a temperature of 100.degree. C.-150.degree. C.

Abstract: A process for the recycling of scrap metal, such as copper wire, comprises the steps of combining the scrap metal with a concentrate of a metal similar to the scrap metal in a pressure vessel (10) and subjecting the metal concentrate to pressure oxidation along with the scrap metal. In one example the scrap metal comprises copper wire and the metal concentrate comprises a copper matte. An apparatus (16) for feeding the scrap metal to the autoclave (10), without interrupting the operation of the autoclave (10) is also provided.

Abstract: A process for the recovery of nickel from a nickel containing ore in which the ore, particularly a laterite ore, is initially leached with an aqueous acid solution, after which the nickel is precipitated as nickel hydroxide by adding a hydroxide to the aqueous acid leach solution containing the nickel, followed by a re-leaching of the nickel with an aqueous ammoniacal solution and recovery of the nickel by a solvent extraction of the nickel from the aqueous ammoniacal solution with an organic phase of a water insoluble oxime extractant dissolved in a water-immiscible hydrocarbon solvent and the nickel recovered by electrowinning the nickel from the aqueous acid stripping solution employed to strip the nickel from the organic phase.

Abstract: The present invention is concerned with a process for extracting and recovering lead or lead derivatives in high purity from various materials containing lead sulphate, and particularly copper smelter flue dusts. The present process also allows the substantially complete recovery or recycling of precious metals otherwise lost in flue dusts wastes.

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 treatment of metallurgical dust and recovery of valuable chemical commodities, comprising the steps of: leaching salts from the dust with water to create a washed EAF dust; reacting the washed EAF dust in a nitric acid solution resulting in a nearly complete dissolution of the zinc, cadmium, copper, magnesium, calcium, manganese and lead from a filtrate; removing iron from the filtrate by raising pH in the system with basic zinc carbonate; removing cadmium, copper and lead in an electrolytic cell, where copper and cadmium are collected at the cathode, and lead is collected at the anode; evaporating and decomposing the filtrate to obtain metal oxides and anhydrous calcium nitrate; leaching the solid residue with water to separate calcium nitrate in a marketable form; removing the zinc from the magnesium and manganese by leaching the residue with an amine solution; stripping the filtrate of ammonium carbonate to yield zinc precipitated as a zinc oxycarbonate; dividing the zinc oxycarbonate into a first stream

Abstract: A method for extracting and reclaiming metals from scrap CdTe photovoltaic cells and manufacturing waste by leaching the metals in dilute nitric acid, leaching the waste with a leaching solution comprising nitric acid and water, skimming any plastic material from the top of the leaching solution, separating the glass substrate from the liquid leachate, adding a calcium containing base to the leachate to precipitate Cd and Te, separating the precipitated Cd and Te from the leachate, and recovering the calcium-containing base.

Abstract: Synthetic Rutile is prepared from raw ilmenite ore by a method comprising activating ilmenite and subjecting it to a multi-stage countercurrent leaching process in hot hydrochloric acid.

Abstract: A process for the extraction of a metal from an ore or concentrate comprises subjecting the ore or concentrate to pressure oxidation in the presence of oxygen and an acidic solution containing halogen ions and a source of bisulphate or sulphate ions, such as H.sub.2 SO.sub.4. The metals which can be extracted by the process comprises copper, as well as non-cuprous metals, such as zinc, and precious metals, such as gold and silver.

Abstract: A metal-containing refractory sulfide ore is split into a first portion and a second portion. The first portion is partially biodigested by a sulfide-digesting microorganism in a biooxidation reactor where the microorganism is acclimated to the sulfide "diet" provided by the ore. The partially digested ore is then combined with the second portion. The resulting material is then dewatered, biooxidized and subjected to a lixiviation process.

Abstract: A process for the extraction of zinc from a sulphide ore or concentrate containing copper and zinc includes subjecting the concentrate to pressure oxidation in the presence of oxygen and an acidic halide solution to obtain a resulting pressure oxidation slurry and subjecting the slurry to a liquid/solid separation step to produce a liquor containing copper and zinc in solution. The liquor containing the copper and zinc is subjected to a first solvent extraction with a copper extractant to remove copper from the solution and to produce a copper depleted raffinate. The copper depleted raffinate is subjected to a second solid extraction with a zinc extractant to produce a zinc depleted raffinate and the zinc depleted raffinate is recycled to the pressure oxidation step.

Abstract: A method for improving the recovery of gold and silver from precious metal ore is disclosed. The method comprises contacting precious metal ore with an aqueous solution containing certain fluoroaliphatic surfactants.

Abstract: The process for removing titanium metal and alloys from nickel metal, nickel metal alloys, cobalt metal and cobalt metal alloys by leaching out the titanium metal and/or alloys with a hydrofluoric acid solution, oxidizing Ti.sup.+3 to Ti.sup.+4 salts in the leached metals or alloys with an aqueous oxidant, and rinsing the leached metal with water to yield nickel metal, nickel metal alloys, cobalt metal, and/or cobalt metal alloys substantially free of titanium and tin.