The present invention is related generally to recovering metals from waste electronics, and more particularly to a process to recover copper and gold commonly found in waste printed circuit boards using a lixiviant containing a weak acid such as citric acid or acetic acid, a particular concentration of table salt and an oxidizer. By using this lixiviant, the copper found in the printed circuit board reacts to form copper salts and gold becomes detached. Importantly this recovery method of copper and gold found in waste PCBs is fast, does not pose environmental hazards and is economically feasible.

A method of recovering gold and copper from a sulfide ore includes (a) removing valuable fines from a product stream from a comminution circuit, such as a crushing and milling circuit, for run of mine ore and producing a valuable fines concentrate stream and (b) processing the remaining comminution product stream after valuable fines removal and producing a valuable coarse concentrate stream.

A synthetic bead for use in mineral separation is described. The synthetic bead has a surface made of a synthetic material such as polymer and the synthetic material is functionalized with molecules having a functional group for attaching mineral particles to the surface in a separation process. The synthetic beads can be placed in flotation cell containing a mixture of water, valuable material and unwanted material or in a pipeline where the mixture is transported from one location to another. The enriched synthetic beads carrying the mineral particles are separated from the unwanted materials in the mixture. The mineral particles are then released from the synthetic beads by means of low pH treatment, ultrasonic agitation, thermal or electromagnetic treatment.

Apparatus for use in, or forming part of, a separation process to be implemented in separation processor technology, the apparatus comprising synthetic bubbles or beads configured with a polymer or polymer-based material functionalized to attach to a valuable material in a mixture so as to form an enriched synthetic bubbles or beads having the valuable material attached thereto, and also configured to be separated from the mixture based at least partly on a difference in a physical property between the enriched synthetic bubbles or beads having the valuable material attached thereto and the mixture.

A method of recovering gold and copper from a sulfide ore includes (a) removing valuable fines from a product stream from a comminution circuit, such as a crushing and milling circuit, for run of mine ore and producing a valuable fines concentrate stream and (b) processing the remaining comminution product stream after valuable fines removal and producing a valuable coarse concentrate stream.

The present invention is related generally to recovering metals from waste electronics, and more particularly to a process to recover copper and gold commonly found in waste printed circuit boards using a lixiviant containing a weak acid such as citric acid or acetic acid, a particular concentration of table salt and an oxidizer. By using this lixiviant, the copper found in the printed circuit board reacts to form copper salts and gold becomes detached. Importantly this recovery method of copper and gold found in waste PCBs is fast, does not pose environmental hazards and is economically feasible.

A method of leaching copper from a copper sulfide ore which includes adding a potential adjustment agent for lowering a potential of a leaching solution obtained after leaching copper from the copper sulfide ore by using iodide ion and iron (III) ion, the leaching solution being stored in a tank for storing the leaching solution.

Disclosed is copper powder having an average primary particle size D of 0.15 to 0.6 m, having a ratio of D to D.sub.BET, D/D.sub.BET, of 0.8 to 4.0 wherein D.sub.BET is a sphere-equivalent average particle diameter calculated from a BET specific surface area, and having no layer for preventing agglomeration on the surface thereof. The copper powder is suitably produced by a method which includes a step of mixing (1) hydrazine and (2) a reactant mixture including a monovalent or divalent copper source and a liquid medium which includes water and an organic solvent having water miscibility and capable of reducing the surface tension of water, to reduce the copper source to form copper particles.

The present application offers a solution to the current problems associated with recovery and recycling of precious metals such as gold and copper from scrap material, discarded articles, and other items. The solution is premised on a microporous chelating polymeric membrane comprising a poly-thiosemicarbazide formed from N,N-diaminopiperazine and a suitable reactant such as diisothiocyanate; the membrane may be formed through the use of a solvent system and non-solvent system. The membrane may be used to separate metal ions from solutions and incorporated in a membrane module.

Disclosed in the present invention is a method for extracting nickel from a high matte nickel leaching residue. The method comprises: firstly, adding a crushed material of a high matte nickel leaching residue to an organic solvent in which sulfur is dissolved, heating same for reaction, and carrying out solid-liquid separation to obtain a first filtrate and a first filter residue; adding the first filter residue to a copper sulfate solution, heating same for reaction, and carrying out solid-liquid separation to obtain a second filtrate and a second filter residue; and evaporating, condensing and concentrating the second filtrate, and filtering same to obtain copper sulfate crystals and a nickel-containing filtrate. Throughout the whole reaction, only a small amount of sulfur and copper sulfate are consumed, and the organic solvent can be recycled.