The extraction system contains secondary amides and alkyl alcohols which are separately used as the extractants for extracting lithium and boron and consist of a single compound or a mixture of two or more compounds, and the total number of carbon atoms in their molecules are 12˜18 and 8˜20 respectively; the extraction system has a freezing point less than 0° C. With a volume ratio of an organic phase and a brine phase being 1˜10:1, at a brine density of 1.25˜1.38 g/cm.sup.3, at a brine pH value of 0˜7 and at a temperature of 0˜50° C., a single-stage or multi-stage countercurrent extraction and a stripping are conducted to obtain a water phase with a low magnesium-lithium ratio, which is subjected to concentration, impurity removal and preparation to get lithium chloride, lithium carbonate, lithium hydroxide and boric acid respectively. Water is used for stripping, greatly reducing the consumption of acid and base.

Systems and methods using solar evaporation to preconcentrate lithium containing brines to at or near lithium saturation, followed by a separation processes to separate lithium from impurities. A separated impurity stream is recycled to a point in the evaporation sequence where conditions are favorable for their precipitation and removal or disposed in a separate evaporation pond or reinjected underground, while a lower impurity stream is transferred to one or more of the removal location, to a subsequent pond in the sequence, or to a lithium plant or concentration facility. Further concentration of lithium by evaporation can then take place because impurities are removed thus eliminating lithium losses due to co-precipitation and achieving significantly higher concentrations of lithium.

Provided is a method that allows for efficient removal of an impurity metal, and further, the recovery of a valuable metal with high efficiency. The method for recovering a valuable metal (Cu, Ni, and Co) includes the steps of: preparing a charge comprising at least a valuable metal as a raw material; heating and melting the raw material to form an alloy and a slag; and separating the slag to recover the alloy containing the valuable metal, wherein the heating and melting of the raw material comprises charging the raw material into a furnace of an electric furnace equipped with an electrode therein, and further melting the raw material by means of Joule heat generated by applying an electric current to the electrode, or heat generation of an arc itself, and thereby separating the raw material into a molten alloy and a molten slag present over the alloy.

Method of separation of a radiometal ion from a target metal ion, comprising a first liquid-liquid extraction step in which an organic phase comprising an extractant and an interfacial tension modifier is mixed with an aqueous phase comprising the radiometal ion and the target metal ion in order that the radiometal ion is at least partially transferred to the organic phase, followed by a first phase separation step, wherein the phase separation is carried out in flow comprising the use of a microfiltration membrane to separate the phases based on the interfacial tension between the phases such that a permeate phase passes through the membrane and a retentate phase does not.

The present disclosure provides a method of recovering copper, molybdenum, and a precious metal value from a metal-bearing material, the method comprising bulk flotation of the metal-bearing material to form a flotation product, wherein the metal-bearing material comprises a copper compound, a molybdenum compound, and at least one precious metal value, pressure oxidizing the flotation product to form a pressure oxidized discharge, separating the pressure oxidized discharge to form a separated liquid and separated solid, extracting molybdenum, via a molybdenum solution extraction, from the separated liquid to form a molybdenum-containing stream and a copper-containing stream, extracting copper, via a copper solution extraction, from the copper-containing stream, and extracting the precious metal value, via a cyanide leaching process, from the separated solid.

A method for recovering a valuable material from a perovskite solar cell includes immersing a perovskite solar cell device in an organic solvent to dissolve a monovalent metal cation, a divalent metal cation, and two halogen anions in the organic solvent, followed by adding an oxidizing agent and conducting a heating treatment to form a solid phase residue and a halogen molecule, dissolving the halogen molecule in deionized water to form a halogen solution, rinsing the solid phase residue with deionized water to obtain a solid phase and a liquid phase, calcining the solid phase into a metal oxide, or mixing the solid phase with the halogen solution to obtain a first metal halide, subjecting the liquid phase to an extraction treatment to form an oil phase layer, followed by conducting a back-extraction treatment, adding the halogen solution, and conducting a vacuum concentration treatment to obtain a second metal halide.

The-use of carbamides as extractants for fully or partially separating uranium(VI) from plutonium(IV) in an aqueous solution obtained by dissolving a spent nuclear fuel in nitric acid, by method of liquid-liquid extraction, without carrying out any reduction of the plutonium(IV) to plutonium(III). The invention also relates to new carbamides. Uses are the processing of spent nuclear fuels based on uranium (especially uranium oxides—UOX) or uranium and plutonium (especially mixed uranium and plutonium oxides—MOX).

The-use of carbamides as extractants for fully or partially separating uranium(VI) from plutonium(IV) in an aqueous solution obtained by dissolving a spent nuclear fuel in nitric acid, by method of liquid-liquid extraction, without carrying out any reduction of the plutonium(IV) to plutonium(III). The invention also relates to new carbamides. Uses are the processing of spent nuclear fuels based on uranium (especially uranium oxides—UOX) or uranium and plutonium (especially mixed uranium and plutonium oxides—MOX).

A method for the recovery of metals from a feed stream containing one or more value metals and lithium, the method comprising: subjecting the feed stream to a sulphuric acid leach to form a slurry comprising a pregnant leach solution of soluble metal salts and a solid residue; separating the pregnant leach solution and the solid residue; subjecting the pregnant leach solution to one or more separate solvent extraction steps, wherein each solvent extraction step recovers one or more value metals from the pregnant leach solution, the remaining pregnant leach solution comprising lithium; and recovery of lithium from the pregnant leach solution.

A method for recovering NiSO.sub.4.6H.sub.2O crystals from a nickel rich organic phase is provided. The method includes contacting a nickel rich organic phase with an aqueous strip solution of sufficient H.sub.2SO.sub.4 concentration to extract nickel from the organic phase and of sufficient Ni.sup.2+ concentration to precipitate NiSO.sub.4.6H.sub.2O crystals and form a nickel lean organic phase. Also provided are methods for recovering NiSO.sub.4.6H.sub.2O crystals that include preceding processing steps, including low temperature pressure oxidation (LTPOX) autoclaving of a nickel sulphide concentrate to afford a pregnant leach solution (PLS).