A process for recovering silver from a mass of scrap of photovoltaic cells. The process includes steps of: providing the scrap of photovoltaic cells, each including a silicon wafer on the upper surface of which an anti-reflective layer and silver lines are provided; immersing the scrap in water or in an aqueous solution; applying ultrasound to cause the silver to detach; sieving the solution to remove the coarse solid fraction containing the silicon wafer residue; and separating the fine solid fraction containing the silver from the solution.

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.

According to embodiments of the present disclosure, there is provided a process of removing aluminum waste from wastewater. The process includes (a) supplying, as a feed, wastewater containing aluminum; (b) separating the wastewater into a liquid component and a sludge component containing the aluminum; (c) reacting the sludge component with sulfuric acid to produce aluminum sulfate; (d) mixing the aluminum sulfate with alcohol to produce aluminum sulfate hydrate; and (e) adding the aluminum sulfate hydrate produced in step (d) to the wastewater of step (a) and/or to another wastewater. The process can cost-effectively remove waste from wastewater and reduce the content of waste contained in the effluent from being discharged.

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 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.

Disclosed in the present invention is a recovery process for a waste battery electrode sheet, the method comprising the following steps: subjecting a waste battery electrode sheet to shearing, drying and cold treatment, and then rolling and screening same to obtain a first positive electrode material and a first waste electrode sheet; subjecting the first waste electrode sheet to shearing, drying and cold treatment, and then rolling and screening same to obtain a second positive electrode material and a second waste electrode sheet; and roasting the first positive electrode material and the second positive electrode material to obtain a positive electrode powder. In the present invention, the aluminum content in the positive electrode material is reduced by means of step-by-step shearing, and the adhesion performance of a waste positive electrode plate binder is then reduced by means of vacuum freeze-drying and spraying with a quick-cooling agent. The aluminum foil of the positive electrode material does not easily break when being broken after vacuum freeze-drying, and the morphology and output of the aluminum foil after primary shearing and secondary shearing are basically unchanged.

An object of the present invention is to provide a novel method for extracting ultra high purity alumina from wastewater. Wastewater is recycled, filtered, concentrated and pretreated in order to mix with alkali solution and extraction agent PX-17, undergoing 2 times of purification, adding control agent SX-1 and high temperature heat treatment to finally obtain ultra high purity nano-alumina particles which purity reaches as 99.999% and particle size reaches as 20200 nm.

Suggested is a method for recovering metals from batteries comprising or consisting of the following steps: (a) providing black mass prepared from spent batteries; (b) providing a culture of microorganisms obtained by using suitable carbon sources to support growth and the production of organic acids, complexing agents or reducing agents; (c) bringing said black mass into contact with said culture of microorganisms or the cell-free supernatant of said culture of microorganisms; (d) depleting said black mass from metals contained therein by bioleaching; (c) separating the depleted black mass from the liquid containing the dissolved metals to obtain a pregnant leach solution; (f) recovering the extracted metals from said pregnant leach solution

A method includes performing pre-treating, comprising fire-roasting or wet-washing, on the processed aluminum scraps of aeronautical aluminum alloy. The method further includes performing pressing formation on the pre-treated processed aluminum scraps of aeronautical aluminum alloy to form block-shaped aluminum scraps. The method further includes performing oxygen-controlled smelting on the block-shaped aluminum scraps in a smelting furnace to form aluminum alloy melt. The method further includes performing casting on the aluminum alloy melt to obtain an aluminum alloy product of meeting component requirements of aeronautical aluminum alloy.

A method for recovering a positive electrode plate of a lithium battery is provided, including steps of: S1, reacting a material of the positive electrode plate with a metal salt in an aqueous solution, wherein the standard electrode potential of a metal in the metal salt is higher than that of aluminum; S2, dissolving and leaching a solid obtained in step S1 with a mixed solution of an acid and a reducing agent; and S3, defluorinating a leaching solution obtained in step S2, then extracting a transition metal in the defluorinated leaching solution, and precipitating and separating out lithium in a raffinate.