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 system for recovering precious metals includes a rotatable drum, recyclable materials, and a separating solution. The rotatable drum is configured to receive recyclable materials. The recyclable materials include non-metallic materials and electronic components, with one or both of the non-metallic materials and the electronic components having attached thereto one or both of base metals and precious metals. The separating solution is disposed in the rotatable drum and is configured to separate the base metals and the precious metals from the electronic components and the non-metallic materials and to separate the electronic components from the non-metallic materials. The rotatable drum is configured to agitate the recyclable materials and to wash the recyclable materials with the separating solution. The electronic components, non-metallic materials, base metals, and precious metals are each separately removable from the separating solution.

A method of maximising the amount of water available for rinsing in a high-chloride heap leach operation which includes the step of using process make-up water in the range of 0.05 to 0.35 m3/ton of ore to rinse leach residue ore, in the heap, thereby to displace a chloride-containing aqueous liquor from the leached ore.

A method of maximising the amount of water available for rinsing in a high-chloride heap leach operation which includes the step of using process make-up water in the range of 0.05 to 0.35 m3/ton of ore to rinse leach residue ore, in the heap, thereby to displace a chloride-containing aqueous liquor from the leached ore.

Provided is a method for easily and inexpensively separating a rare earth element contained in an aqueous solution.

Disclosed herein are methods of recycling elements, such as, e.g., lithium and/or nickel, from a solution, such as, e.g., methods of recovering reusable lithium and nickel from a waste stream produced by the delithiation of a lithium nickel oxide material.

Disclosed herein are methods of recycling elements, such as, e.g., lithium and/or nickel, from a solution, such as, e.g., methods of recovering reusable lithium and nickel from a waste stream produced by the delithiation of a lithium nickel oxide material.

It is provided a process of producing amorphous silica from a raw material, such as serpentine, containing silica comprising the steps of mixing the raw material with a hydrochloric acid solution; leaching the raw material obtaining a slurry comprising a liquid fraction and a solid fraction containing silica and minerals; separating the liquid fraction and the solid fraction; removing the minerals from the solid fraction by magnetic separation producing a purified solid silica; drying the purified solid silica; and heating the purified solid silica to remove hydroxyl groups from the silica surface and reducing specific surface area of the resulting amorphous silica.

It is provided a process of producing amorphous silica from a raw material, such as serpentine, containing silica comprising the steps of mixing the raw material with a hydrochloric acid solution; leaching the raw material obtaining a slurry comprising a liquid fraction and a solid fraction containing silica and minerals; separating the liquid fraction and the solid fraction; removing the minerals from the solid fraction by magnetic separation producing a purified solid silica; drying the purified solid silica; and heating the purified solid silica to remove hydroxyl groups from the silica surface and reducing specific surface area of the resulting amorphous silica.

The invention relates to a method for recovering precious metals from electronic waste utilising biometallurgical techniques. In one aspect, a method of recovering one or more target metals from electronic waste, includes (a) removing at least a portion of non-target material from the electronic waste or grinding to a preselected size particle to give pre-processed electronic waste; (b) contacting the pre-processed electronic waste with a lixiviant such that at least a portion of the target metal(s) dissolve into the lixiviant to produce a pregnant solution; (c) contacting a microorganism with the pregnant solution such that at least a portion of the target metal(s) ions biosorb to the microorganism wherein the microorganism becomes metal laden and the pregnant solution becomes barren; (d) substantially separating the metal laden microorganism from the barren solution; and (e) recovery of the target metal(s) from the metal laden microorganism.