Disclosed is a method for recovering a waste lithium cobalt oxide battery, the method comprising: feeding a lithium cobalt oxide battery black powder in a column-shaped container, adding a first acid to the column-shaped container for heat leaching until solids in the column-shaped container are not reduced any more so as to obtain a first leachate and leaching residues, wherein the first acid is a weak acid, and a filtering structure is arranged at the bottom of the column-shaped container; and adding a second acid to the column-shaped container containing the leaching residues for heat leaching until solids in the column-shaped container are not reduced any more so as to obtain a second leachate and graphite, wherein the second acid is a strong acid. According to the present invention, consumption of an inorganic strong acid can be reduced, emission of strong acid gas is reduced, and green and low-carbon heat leaching of the black powder is achieved.

A method of selectively removing impurities from a scandium-containing feed solution includes contacting an aqueous scandium-containing solution with an organic solvent stream containing an extractant, thereby forming a loaded organic solvent stream containing the impurity or impurities while leaving the scandium in the raffinate. The aqueous stream containing the scandium is washed, diluted and has inorganic salts added before being contacted with a second organic solvent stream to extract the scandium selectively, and followed by stripping the scandium from the scandium-containing loaded organic extractant stream by adding oxalic acid to the loaded organic extractant stream to form scandium oxalate.

A method for isolating scandium values is provided. The method includes providing a scandium-bearing ore; subjecting the scandium-bearing ore to an acid leaching process, thereby obtaining a leachate, wherein the pH of the leachate is less than 1.5; extracting scandium values from the leachate with an organic solvent, thereby obtaining a scandium-loaded organic solvent, wherein the leachate contains iron and scandium ions, and wherein the organic solvent contains a primary amine; stripping the scandium values from the scandium-loaded solvent with a stripping solution containing an acid and a salt, thereby obtaining a scandium-loaded stripping solution, wherein the acid is selected from the group consisting of sulfuric acid, nitric acid, hydrochloric acid and phosphoric acid, wherein the salt is selected from the group consisting of alkali chlorides, alkali earth chlorides, alkali nitrates, alkali sulfates, alkali phosphates, ammonium chlorides, ammonium nitrates, ammonium sulfates and ammonium phosphates, and wherein the salt comprises a cation selected from the group consisting of Na, K, Li, NH.sub.4 and Mg; and processing the scandium-loaded stripping solution to yield scandium oxide.

A method of selectively removing impurities from a scandium-containing feed solution includes contacting an aqueous scandium-containing solution with an organic solvent stream containing an extractant, thereby forming a loaded organic solvent stream containing the impurity or impurities while leaving the scandium in the raffinate. The aqueous stream containing the scandium is washed, diluted and has inorganic salts added before being contacted with a second organic solvent stream to extract the scandium selectively, and followed by stripping the scandium from the scandium-containing loaded organic extractant stream by adding oxalic acid to the loaded organic extractant stream to form scandium oxalate.

Provided is a method of recovering copper and one or more precious metals comprising leaching copper-bearing ore and/or concentrate under atmospheric or slightly pressurized conditions at a temperature below the boiling point of the leach solution in a sulfuric acidic solution in the presence of one or more alkali metal or alkali earth metal halides, whereby the total halide concentration is from 30 to 115 g/L, to dissolve copper and to obtain a leaching liquor comprising copper, sulfur species, and halides in solution. The leaching liquor is then subjected to a solid-liquid separation after which a first aqueous pregnant leach solution and a copper depleted leaching residue are obtained. Copper is purified by solvent extraction from the first aqueous pregnant leach solution to obtain a first copper-containing loaded organic solution and a first aqueous raffinate. The copper containing loaded organic solution is stripped and copper is recovered.

A method for isolating scandium values is provided. The method includes extracting scandium values from a leachate with an organic solvent, thereby obtaining a scandium-loaded organic solvent, wherein the leachate contains iron and scandium ions, and wherein the organic solvent contains a primary amine. The scandium values are then stripped from the scandium-loaded solvent with a stripping solution containing an acid and a salt.

A method for extracting and separating a rare-earth element by extracting and separating the rare-earth element from an aqueous solution of rare-earth nitrate into n-heptane, with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester trialkyl methyl ammonium or di-2-ethylhexyl phosphoric acid trialkyl methyl ammonium as an extractant, and n-heptane as a diluent by contacting the aqueous solution of rare-earth nitrate with the extractant and the diluent to extract and separate the rare earth element into n-heptane from the aqueous solution of rare earth nitrate.

Provided is a method for purification of manganese pregnant leach solution (PLS) using solvent extraction (SX). The method broadly comprises the steps of providing a partially purified aqueous pregnant leach solution (PLS), using an SX load stage to form a first organic mixture which forms a loaded organic phase comprising all of the manganese from the PLS, performing two stages of SX scrubbing to form a third organic mixture which is substantially free of impurities, performing SX stripping to transfer the manganese content of the scrubbed organic phase into a clean aqueous phase, and producing high purity manganese sulphate monohydrate (HPMSM) crystals from the clean aqueous phase.

What is provided is a method for separating cobalt and nickel including: a crushing and sorting step of crushing and classifying the lithium ion secondary battery to obtain an electrode material containing at least cobalt, nickel, copper, and lithium; a leaching step of immersing the electrode material in a processing liquid containing sulfuric acid and hydrogen peroxide to obtain a leachate; a copper separation step of adding a hydrogen sulfide compound to the leachate with stirring and subsequently carrying out solid-liquid separation to obtain an eluate containing cobalt and nickel and a residue containing copper sulfide; and a cobalt/nickel separation step of adding an alkali metal hydroxide to the eluate to adjust a pH and subsequently, adding a hydrogen sulfide compound with stirring and carrying out solid-liquid separation to obtain a precipitate containing cobalt sulfide and nickel sulfide and a residual liquid containing lithium.