A process disclosed herein is related to the isolation and purification of substantially pure chemicals, including silica gel, sodium silicate, aluminum silicate, iron oxide, and rare earth elements (or rare earth metals, REEs), from massive industrial waste coal ash. In one embodiment, the process includes a plurality of caustic extractions of coal ash at an elevated temperature, followed by an acidic treatment to dissolve aluminum silicate and REEs. The dissolved aluminum silicate is precipitated out by pH adjustment as a solid product while REEs remain in the solution. REEs are captured and enriched using an ion exchange column. Alternatively, the solution containing aluminum silicate and REEs is heated to produce silica gel, which is easily separated from the enriched REEs solution. REEs are then isolated and purified from the enriched solution to afford substantially pure individual REE by a ligand-assisted chromatography. Additionally, a simplified process using one caustic extraction and one acidic extraction with an ion exchange process was also investigated and optimized to afford a comparable efficiency.

A process disclosed herein is related to the isolation and purification of substantially pure chemicals, including silica gel, sodium silicate, aluminum silicate, iron oxide, and rare earth elements (or rare earth metals, REEs), from massive industrial waste coal ash. In one embodiment, the process includes a plurality of caustic extractions of coal ash at an elevated temperature, followed by an acidic treatment to dissolve aluminum silicate and REEs. The dissolved aluminum silicate is precipitated out by pH adjustment as a solid product while REEs remain in the solution. REEs are captured and enriched using an ion exchange column. Alternatively, the solution containing aluminum silicate and REEs is heated to produce silica gel, which is easily separated from the enriched REEs solution. REEs are then isolated and purified from the enriched solution to afford substantially pure individual REE by a ligand-assisted chromatography. Additionally, a simplified process using one caustic extraction and one acidic extraction with an ion exchange process was also investigated and optimized to afford a comparable efficiency.

The present invention relates to a method for recycling iron and aluminum in a nickel-cobalt-manganese solution. The method comprises the following steps: leaching a battery powder and removing copper therefrom to obtain a copper-removed solution, and adjusting the pH value in stages to remove iron and aluminum, so as to obtain a goethite slag and an iron-aluminum slag separately; mixing the iron-aluminum slag with an alkali liquor, and heating and stirring same to obtain an aluminum-containing solution and alkaline slag; and heating and stirring the aluminum-containing solution, introducing carbon dioxide thereto and controlling the pH value to obtain aluminum hydroxide and an aluminum-removed solution.

A process disclosed herein is related to the isolation and purification of substantially pure chemicals, including silica gel, sodium silicate, aluminum silicate, iron oxide, and rare earth elements (or rare earth metals, REEs), from massive industrial waste coal ash. In one embodiment, the process includes a plurality of caustic extractions of coal ash at an elevated temperature, followed by an acidic treatment to dissolve aluminum silicate and REEs. The dissolved aluminum silicate is precipitated out by pH adjustment as a solid product while REEs remain in the solution. REEs are captured and enriched using an ion exchange column. Alternatively, the solution containing aluminum silicate and REEs is heated to produce silica gel, which is easily separated from the enriched REEs solution. REEs are then isolated and purified from the enriched solution to afford substantially pure individual REE by a ligand-assisted chromatography. Additionally, a simplified process using one caustic extraction and one acidic extraction with an ion exchange process was also investigated and optimized to afford a comparable efficiency.

A process for the isolation and purification of substantially pure chemicals, including silica gel, sodium silicate, aluminum silicate, iron oxide, and rare earth elements (or rare earth metals, REEs), from massive industrial waste coal ash including a plurality of caustic extractions of coal ash at an elevated temperature, followed by an acidic treatment to dissolve aluminum silicate and REEs. Dissolved aluminum silicate is precipitated out by pH adjustment as a solid product while REEs remain in the solution. REEs are captured and enriched using an ion exchange column. Alternatively, the solution containing aluminum silicate and REEs is heated to produce silica gel, which is separated from the enriched REEs solution. REEs are then isolated and purified from the enriched solution to afford substantially pure individual REE by a ligand-assisted chromatography.

A process for the isolation and purification of substantially pure chemicals, including silica gel, sodium silicate, aluminum silicate, iron oxide, and rare earth elements (or rare earth metals, REEs), from massive industrial waste coal ash including a plurality of caustic extractions of coal ash at an elevated temperature, followed by an acidic treatment to dissolve aluminum silicate and REEs. Dissolved aluminum silicate is precipitated out by pH adjustment as a solid product while REEs remain in the solution. REEs are captured and enriched using an ion exchange column. Alternatively, the solution containing aluminum silicate and REEs is heated to produce silica gel, which is separated from the enriched REEs solution. REEs are then isolated and purified from the enriched solution to afford substantially pure individual REE by a ligand-assisted chromatography.

A process disclosed herein is related to the isolation and purification of substantially pure chemicals, including silica gel, sodium silicate, aluminum silicate, iron oxide, and rare earth elements (or rare earth metals, REEs), from massive industrial waste coal ash. In one embodiment, the process includes a plurality of caustic extractions of coal ash at an elevated temperature, followed by an acidic treatment to dissolve aluminum silicate and REEs. The dissolved aluminum silicate is precipitated out by pH adjustment as a solid product while REEs remain in the solution. REEs are captured and enriched using an ion exchange column. Alternatively, the solution containing aluminum silicate and REEs is heated to produce silica gel, which is easily separated from the enriched REEs solution. REEs are then isolated and purified from the enriched solution to afford substantially pure individual REE by a ligand-assisted chromatography. Additionally, a simplified process using one caustic extraction and one acidic extraction with an ion exchange process was also investigated and optimized to afford a comparable efficiency.

Disclosed is a method of recovering rare earth, aluminum and silicon from rare earth-containing aluminum-silicon scrap. The method comprises: S1, acid-leaching the rare earth-containing aluminum-silicon scrap with an inorganic acid aqueous solution to obtain a silicon-rich slag and acid leached solution containing rare earth and aluminum element; S2, adding an alkaline substance into the acid leached solution containing the rare earth and aluminum element and controlling a PH value of the acid leaching solution between 3.5 to 5.2, performing a solid-liquid separation to obtain a aluminum hydroxide-containing precipitate and a rare earth-containing solution filter; S3, reacting the aluminum hydroxide containing precipitate with sodium hydroxide to obtain sodium metaaluminate solution and aluminum-silicon slag, and preparing a rare earth compound product with the rare earth-containing filtrate. The method dissolves an the aluminum and the rare earth with the acid and then via step wise alkaline conversion, convert aluminum icons to an aluminum hydroxide precipitate separated from rare earth ions, and then adds excessive amounts of sodium hydroxide to convert the aluminum hydroxide to a sodium metaaluminate solution, thereby realizing high-efficiency recovery of both rare earth and aluminum while significantly reducing the consumption of the sodium hydroxide and thus recovery cost.

Disclosed is a method of recovering rare earth, aluminum and silicon from rare earth-containing aluminum-silicon scrap. The method comprises: S1, acid-leaching the rare earth-containing aluminum-silicon scrap with an inorganic acid aqueous solution to obtain a silicon-rich slag and acid leached solution containing rare earth and aluminum element; S2, adding an alkaline substance into the acid leached solution containing the rare earth and aluminum element and controlling a PH value of the acid leaching solution between 3.5 to 5.2, performing a solid-liquid separation to obtain a aluminum hydroxide-containing precipitate and a rare earth-containing solution filter; S3, reacting the aluminum hydroxide containing precipitate with sodium hydroxidee to obtain sodium metaaluminate solution and aluminum-silicon slag, and preparing a rare earth compound product with the rare earth-containing filtrate. The method dissolves an the aluminum and the rare earth with the acid and then via step wise alkaline conversion, convert aluminum icons to an aluminum hydroxide precipitate separated from rare earth ions, and then adds excessive amounts of sodium hydroxide to convert the aluminum hydroxide to a sodium metaaluminate solution, thereby realizing high-efficiency recovery of both rare earth and aluminum while significantly reducing the consumption of the sodium hydroxide and thus recovery cost.

A process disclosed herein is related to the isolation and purification of substantially pure chemicals, including silica gel, sodium silicate, aluminum silicate, iron oxide, and rare earth elements (or rare earth metals, REEs), from massive industrial waste coal ash. In one embodiment, the process includes a plurality of caustic extractions of coal ash at an elevated temperature, followed by an acidic treatment to dissolve aluminum silicate and REEs. The dissolved aluminum silicate is precipitated out by pH adjustment as a solid product while REEs remain in the solution. REEs are captured and enriched using an ion exchange column. Alternatively, the solution containing aluminum silicate and REEs is heated to produce silica gel, which is easily separated from the enriched REEs solution. REEs are then isolated and purified from the enriched solution to afford substantially pure individual REE by a ligand-assisted chromatography. Additionally, a simplified process using one caustic extraction and one acidic extraction with an ion exchange process was also investigated and optimized to afford a comparable efficiency.