Abstract

Described is a method of recovering a metal from a substrate having a metal sulphide, metal oxide, or combination thereof, by contacting the substrate with an aqueous oxidant to oxidize the metal sulphide to elemental sulphur and oxidized metal or convert the complex metal oxide to a metal salt, contacting the oxidized metal or simple metal oxide with ammonium hydroxide to form soluble a ammine complex of the metal to obtain a leachate and residual solids; separating the leachate from the residual solids; and recovering the metal.

IPC Classes  ?

• C22B 3/14 - Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic alkaline solutions containing ammonia or ammonium salts
• C22B 3/00 - Extraction of metal compounds from ores or concentrates by wet processes
• C22C 18/00 - Alloys based on zinc
• C22C 11/00 - Alloys based on lead
• C22C 9/00 - Alloys based on copper
• C22C 5/06 - Alloys based on silver
• C22C 5/02 - Alloys based on gold
• C22B 15/00 - Obtaining copper

Abstract

Described is a method of recovering a metal from a substrate having a metal sulphide, metal oxide, or combination thereof, by contacting the substrate with an aqueous oxidant to oxidize the metal sulphide to elemental sulphur and oxidized metal or convert the complex metal oxide to a metal salt, contacting the oxidized metal or simple metal oxide with ammonium hydroxide to form soluble a ammine complex of the metal to obtain a leachate and residual solids; separating the leachate from the residual solids; and recovering the metal.

IPC Classes  ?

• C22B 3/14 - Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic alkaline solutions containing ammonia or ammonium salts
• C22B 3/00 - Extraction of metal compounds from ores or concentrates by wet processes
• C22B 15/00 - Obtaining copper
• C22C 5/02 - Alloys based on gold
• C22C 5/06 - Alloys based on silver
• C22C 9/00 - Alloys based on copper
• C22C 11/00 - Alloys based on lead
• C22C 18/00 - Alloys based on zinc

Abstract

Described is a method of recovering a metal from a substrate having a metal sulphide, metal oxide, or combination thereof, by contacting the substrate with an aqueous oxidant to oxidize the metal sulphide to elemental sulphur and oxidized metal or convert the complex metal oxide to a metal salt, contacting the oxidized metal or simple metal oxide with ammonium hydroxide to form soluble a ammine complex of the metal to obtain a leachate and residual solids; separating the leachate from the residual solids; and recovering the metal.

IPC Classes  ?

• C22B 3/04 - Extraction of metal compounds from ores or concentrates by wet processes by leaching
• C22B 3/22 - Treatment or purification of solutions, e.g. obtained by leaching by physical processes, e.g. by filtration, by magnetic means
• C22B 3/44 - Treatment or purification of solutions, e.g. obtained by leaching by chemical processes
• C22B 7/00 - Working-up raw materials other than ores, e.g. scrap, to produce non-ferrous metals or compounds thereof
• C22B 11/00 - Obtaining noble metals
• C22B 13/00 - Obtaining lead
• C22B 15/00 - Obtaining copper

Abstract

Zinc and lead are usually concomitantly present in Zn—Pb ores and tailings. A novel non-polluting hydrometallurgical process for selectively leaching and recovering zinc (Zn) from a composite lead (Pb) and zinc sulphide containing mineral, crushed untreated rock or unconsolidated mineral particles, mill tailings and/or agglomerated or unagglomerated sulphidic zinc containing waste material without necessitating smelting and refining operation has been developed. A combination of selected oxidant and alkali metal hydroxide has been found effective. A leachant consisting of e.g. a mixture of sodium hydroxide (NaOH) and sodium hypochlorite (NaOCl) is employed to selectively dissolve zinc sulphide at high pH at standard temperature and pressure (STP). The kinetics of leaching along with the effect of varying concentration (preferably of sodium hydroxide and sodium hypochlorite) were systematically investigated. Feed ore containing diverse set of minerals e.g. sulphides and carbonates can also be conveniently treated to selectively and almost quantitatively recover zinc as high purity zinc carbonate. This technology can be employed either in-situ or ex-situ based on the amenability of a particular type of mineral deposit or feed ore.

IPC Classes  ?

• C01G 9/00 - Compounds of zinc
• C22B 19/02 - Preliminary treatment of oresPreliminary refining of zinc oxide
• C22B 3/00 - Extraction of metal compounds from ores or concentrates by wet processes

Abstract

A method of preparing insoluble transition metal compound particles is described, comprising: providing a transition metal salt solution having the formula (TM)(S) wherein TM is one or more of Mn, Ni, Co, Mg, Zn, Ca, Sr, Cu, Zr, P, Fe, Al, Ga, In, Cr, Ge or Sn; providing a source of a carbonate-, hydroxide-, phosphate-, oxyhydroxide- or oxide-based anionic compound wherein the anionic component, represented by S', is reactive with TM to form the particles; adding the transition metal salt solution and anionic compound to a reaction chamber; and subjecting the chamber to sonication at an intensity of about 0.1 to about 50 W/mL. In an exemplary embodiment, MnCO3 particles are formed from: MnSO4; and Na2CO3 and/or NH4HCO3, wherein the ratio of MnSO4 to Na2CO3 and/or NH4HCO3 is from about 1 : 1.5 to 1.5: 1. The particles may have narrow size distribution and a tap density of about 1.7 -2.3 g/mL.

IPC Classes  ?

• C01G 45/00 - Compounds of manganese
• B22F 9/24 - Making metallic powder or suspensions thereofApparatus or devices specially adapted therefor using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
• C01B 31/24 - Methods for the preparation of carbonates or bicarbonates in general

Abstract

Zinc and lead are usually concomitantly present in Zn-Pb ores and tailings. A novel non-polluting hydrometallurgical process for selectively leaching and recovering zinc (Zn) from a composite lead (Pb) and zinc sulphide containing mineral, crashed untreated rock or unconsolidate mineral particles, mill tailings and/or agglomerated or unagglomerated sulphidic zinc containing waste material without necessitating smelting and refining operation has been developed. This technology can be employed either in-situ or ex-situ based on the amenability of a particular type of mineral deposit or feed ore. A process and leachant composition are provided for selective leaching of zinc from mixtures and ores containing zinc sulphide comprising contacting the mixture or ore with an aqueous leachant comprising: 1) an oxidant selected to oxidize the sulphur present only to elemental sulphur, and 2) alkali metal hydroxide in amounts sufficient to form soluble alkali metal zincate; extending the contact time between leachant and solids to give the desired zinc recovery and selectivity in the leachate while maintaining operative reagent concentrations; separating the desired leachate from the residual solids; and recovering zinc from the leachate.

IPC Classes  ?

• C22B 19/20 - Obtaining zinc otherwise than by distilling
• C22B 3/04 - Extraction of metal compounds from ores or concentrates by wet processes by leaching
• C22B 3/12 - Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic alkaline solutions

Abstract

Calcium (Ca), manganese (Mn) and magnesium (Mg) carbonate plus lead (Pb) and zinc (Zn) sulphide minerals in a permeable host, crushed ore, concentrates or as mine discharge tailing are selectively solution mined (in-situ or ex-situ) with a selected acid e.g. acetic acid to extract Ca, Mn, and Mg followed by multivalent oxidizing salts e.g. ferric salts to extract Pb and Zn sequentially. For in-situ leaching, an inter relationship has been identified between pressure, temperature, target depth and leachate concentration such that carbonate leaching is performed in a manner to prevent carbon dioxide gas (CO2) discharge thereby plugging host rock permeability avenues to preclude further leaching. This requires controlling the rate of acetic acid leaching to be in step with availability of solution to dissolve the resulting discharged CO2. Sulphide leaching is subsequently conducted on the carbonate-depleted host. The two resulting leachates are chemically treated to selectively recover extracted minerals as value added industrially ready products. The in situ method is particularly advantageous in preparing the high purity manganese products necessary for lithium ion batteries because it prevents occurrence of very fine metallic particles in the products that may happen during conventional mining. Alternatively, the in situ carbonate recovery steps can be independently employed; all in an environmentally friendly manner.

IPC Classes  ?

• C22B 3/04 - Extraction of metal compounds from ores or concentrates by wet processes by leaching
• C22B 13/00 - Obtaining lead
• C22B 19/00 - Obtaining zinc or zinc oxide
• C22B 26/20 - Obtaining alkaline earth metals or magnesium
• C22B 47/00 - Obtaining manganese