The present invention related to generally to a process to recover metals from waste electronics, and more particularly a process to recover gold from waste electronics. The gold is first delaminated in a first step using a solution containing a weak acid in combination with an oxidizer. The second step isolates and purifies the delaminated gold from the chip debris using solvents, water and a wetting agent/surfactant. The proposed two step method of gold recovery from electronic waste is effective without the need for strong or costly chemicals or leaching.

The present disclosure is related to the recovery of metal(s) using molten salt and related systems.

A process for the winning of at least one of gold, silver, and at least one platinum metal includes introducing at least one starting material containing at least one of gold, silver, and at least one platinum metal into an aqueous solution containing at least one nitrile, and producing hydroxyl radicals in the aqueous solution.

The process and practice of extracting and/or removing precious metals and/or other elements from landfills or other environments designated for the processing, storing, and final disposal of municipal solid or construction waste. This process applies to all landfill operations, when the intent is to recover precious metals (e.g. Gold, Silver, Platinum, Palladium, Rhodium, etc.) or other valuable soil materials (due to decades or centuries of decomposing trash), and includes the inadvertent discovery of such materials during land reclamation or remediation activities that require the use of earth moving equipment/machinery such as excavators, front end loaders, etc.

A method for removing metal and/or precious metal-containing depositions from substrates, wherein said substrate is subjected to treatment with an organo amine protectant component P and an inorganic active component A. Component P may be formed in situ by reaction with component R. Component P is an organic amine and/or organic amine hydrohalide and/or organic ammonium halide (preferably diisopropylamine hydrochloride), component A is an inorganic compound (preferably inorganic acid or a mixture thereof) and component R is an organic compound that can be split along the C—N bond by the component A into an organic amine (preferably dimethylformamide or N-methyl pyrrolidone). The metals in the form of organo-metallic complexes and/or metalorganic compounds are isolated and/or separated by means of different chemical reactions (preferably reduction reactions) and/or biosorption (preferably with seaweed or yeast). The isolated and/or separated organo-metallic complexes and/or metalorganic compounds are subjected to refinement process to form pure metals and/or pure precious metals. The substrates remain intact after the treatment.

Systems and methods for the recovery of silver are generally described. Certain embodiments are related to innovations newly developed within the context of the present invention that exploit the ability of elemental silver (i.e., silver metal in an uncharged, unreacted state—and in certain cases, in relatively high purities) to be recovered from liquids (e.g., suspensions and/or solutions) containing non-elemental silver (i.e., silver ions, silver salts, silver complexes, silver compounds, etc.), by exposing the non-elemental silver to certain reducing agents.

The present invention relates to a method for recovering metals using an adsorbent, which comprises preparing a leachate comprising metal ions and cyanides, wherein the metal ions comprise gold ions and copper ions; and in a state where the leachate has a cyanide (CN) concentration of 0.1 ppm or greater, adding to the leachate an adsorbent, which has an open circuit potential value between the open circuit potential value of the gold ions and that of the copper ions; and selectively adsorbing the copper ions to the adsorbent.

A method for the hydrometallurgical processing of a noble metal-tin alloy consisting of (i) 0.45 to 25% by weight of at least one metal A selected from the group consisting of gold and platinum, (ii), 35 to 99.2% by weight of at least one metal B selected from the group consisting of palladium, silver, and copper, (iii) 0.3 to 30% by weight tin, and (iv) 0 to 50% by weight of at least one element other than gold, platinum, palladium, silver, copper, and tin, and has a weight ratio of metal A:tin of 0.7:1, comprising the steps of:

(a1) specifically selecting a noble metal-tin alloy
or
(a2) specifically producing a noble metal-tin alloy;
(b) dissolving nitric acid-soluble components of the noble metal-tin alloy with nitric acid while forming a nitric acid-containing solution comprising the at least one metal B in the form of the dissolved nitrate, and an undissolved residue;
(c) separating the undissolved residue from the nitric acid-containing solution; and
(d) dissolving the separated residue in a medium that comprises hydrochloric acid and at least one oxidation agent.

The disclosure discloses an irreversible covalent organic framework for efficient and selective gold recovery and a preparation method thereof, and belongs to the technical field of precious metal recovery from an aqueous solution. In the disclosure, metal trifluoromethanesulfonate is used as a catalyst, and a solvothermal method is used to prepare a mother covalent organic framework, and then the corresponding structural unit is used to perform an exchange reaction to prepare an irreversible amide-linked covalent organic framework material. The disclosure solves the problem of preparation of high-stability irreversible covalent organic framework, the introduced amide bond gives the covalent organic framework the ability to quickly and selectively recover precious metal gold from an aqueous solution, and the covalent organic framework can be used repeatedly. The application of the covalent organic framework as an efficient adsorbent in the field of adsorption and separation is expanded, and a new material is provided for efficient recovery or removal of metal salts.

The present invention relates, on one hand, to a metal cementing apparatus (1) formed by a vessel (2) with a liquid phase formed by a solution (3) containing noble metal, and a solid phase formed by a cementing metal or a less noble metal in contact with the solution (3), where one of said phases moves at a high speed with respect to the other one, and the difference in speeds allows the cementation of the noble metal on the solid phase, and the simultaneous detachment and separation thereof, and comprises means for generating the movement of at least the phase with the high speed and removing means for removing the precipitated noble metal. The invention describes, on the other hand, a continuous cementation method consisting of passing a continuous flow of solution in a vessel (2); reacting the solid phase with the liquid phase, where one of said phases moves at a high speed with respect to the other one, causing the fixing of the noble metal and the simultaneous detachment thereof; removing the precipitated noble metal.