A method for producing a collector alloy comprising 25 to 100 wt % precious metal in total, comprising 0 to <97 wt % of the precious metal silver, 0 to 75 wt % of at least one precious metal selected from gold, platinum, rhodium and palladium, and 0 to 75 wt % of at least one non-precious metal selected from copper, iron, tin and nickel, or for producing pure silver, comprising the steps of: (1) providing precious metal sweeps; (2) providing a flux which, during collective melting with the refractory inorganic material from the precious metal sweeps provided in step (1); (3) collective melting of the materials provided in steps (1) and (2) at a temperature in the range of from 1300 to 1600° C., forming a melt comprising at least two phases of different densities arranged one above the other; and. (4) separating the upper phase and the lower phase.

Provided is a platinum-group metal recovery method for efficiently recovering a platinum-group metal. The method for recovering a platinum-group metal includes an immobilization step of causing a molten product of a raw material containing a platinum-group metal, a molten product of a carbonate or hydroxide of an alkali metal, a molten product of an oxide, and a ceramic material to make contact with each other so as to immobilize the platinum-group metal on the ceramic material.

The invention is directed to a process and apparatus for metal refining, in particular for refining a mixture of conductive particles, such as heavy non-ferrous particles. In accordance with the invention a feed containing a mixture of conductive particles is fed to a dissolution unit, wherein the less noble metal is separated from a metal of interest in the presence of one or more acids or complexing agents, thus producing a stream having a concentrated less noble metal and producing a conductive stream containing a metal of interest. The conductive stream is then fed to a refining unit, wherein the conductive stream is separated in a stream of concentrated metal(s) of interest and a stream of concentrated conductive particles.

A method for recovery of gold from gold-containing materials, such as electronic waste material, minerals and sands is described. The method includes crushing the gold containing material to obtain a particulate material. The particulate material is then preheated in an oxygen-containing gas environment in a preheating zone. The method also includes mixing the oxidized particulate material with a chlorine-containing material and treating the mixture in a reaction zone. The treatment is carried out by heating the mixture to provide thermal decomposition of the chlorine-containing material and produce a chlorine-containing gas mixture, and by applying an electromagnetic field to the chlorine-containing gas mixture to provide ionization of chlorine. A volatile gold-containing chloride product, produced in the reaction zone as a result of a chemical reaction between gold and chlorine ions, is then cooled to convert the volatile gold-containing chloride product into solid phase gold-containing materials.

A method for comprehensively processing noble lead provided and utilizes two instances of vacuum distillation to realize an open circuit of arsenic, lead, antimony and bismuth and the high-efficiency enrichment of precious metals of gold and silver, and can obtain elemental arsenic, a lead-bismuth-antimony alloy, a silver alloy and a copper alloy, respectively. The lead-bismuth-antimony alloy, the silver alloy and the copper alloy are processed by oxidation refining, electrorefining and chlorination refining to obtain refined lead, refined antimony, antimony trioxide, electrolytic silver and electrolytic copper, and to realize gold enrichment. The entire process has advantages of high metal direct yield, low energy consumption, short flow chart, simple equipment, etc., and vacuum distillation belongs to a physical process in which the alloy can be separated only by means of the difference in saturated vapor pressure between the metals, without generation of wastewater, waste gas and waste residue.

A method for recovery of gold from gold-containing materials, such as electronic waste material, minerals and sands is described. The method includes crushing the gold containing material to obtain a particulate material. The particulate material is then preheated in an oxygen-containing gas environment in a preheating zone. The method also includes mixing the oxidized particulate material with a chlorine-containing material and treating the mixture in a reaction zone. The treatment is carried out by heating the mixture to provide thermal decomposition of the chlorine-containing material and produce a chlorine-containing gas mixture, and by applying an electromagnetic field to the chlorine-containing gas mixture to provide ionization of chlorine. A volatile gold-containing chloride product, produced in the reaction zone as a result of a chemical reaction between gold and chlorine ions, is then cooled to convert the volatile gold-containing chloride product into solid phase gold-containing materials.

Process for removing inorganically and/or organically-bound carbon from a precious metal-containing composition inside an oven chamber comprising at least one direct burner and at least one exhaust gas conduit, characterised by the sequence of steps of: a) providing a precious metal-containing composition comprising fractions of inorganically and/or organically-bound carbon inside the oven chamber; b) closing the oven chamber; c) heating the content of the oven chamber by means of at least one direct burner in order to establish a temperature T1 in the range of 450 C. to 1,000 C. and maintaining temperature T1 for 5 min-48 h; whereby, once the oven chamber is closed, any gas exchange between the oven chamber and the surroundings can take place only via the at least one direct burner and the at least one exhaust gas conduit.

A method for comprehensively processing noble lead provided and utilizes two instances of vacuum distillation to realize an open circuit of arsenic, lead, antimony and bismuth and the high-efficiency enrichment of precious metals of gold and silver, and can obtain elemental arsenic, a lead-bismuth-antimony alloy, a silver alloy and a copper alloy, respectively. The lead-bismuth-antimony alloy, the silver alloy and the copper alloy are processed by oxidation refining, electrorefining and chlorination refining to obtain refined lead, refined antimony, antimony trioxide, electrolytic silver and electrolytic copper, and to realize gold enrichment. The entire process has advantages of high metal direct yield, low energy consumption, short flow chart, simple equipment, etc., and vacuum distillation belongs to a physical process in which the alloy can be separated only by means of the difference in saturated vapor pressure between the metals, without generation of wastewater, waste gas and waste residue.

The present invention relates to a method for selectively precipitating and extracting gold in aqueous solution by niacin. Aqueous Au.sup.3+ is precipitated selectively as it's complex from gold containing acidic mixtures by biomolecule niacin, with the formula [AuCl.sub.4].sup.[2Niacin+H].sup.+. After precipitation, the complex is separated from impurities by filtration. Recovered complex is reduced by using a reductant like sodium metabisulfite (Na.sub.2S.sub.2O.sub.5) to recover gold metal. The method is highly cost-effective, sustainable and recovers about 96.5% of gold in 2 minutes from an electronic waste composed of Au. Cu and Ni. The method is also employed to extract gold from nanomaterials waste generated in laboratories.

A method for recovering valuable metals and simultaneously preparing ceramsite by roasting cyanide tailing belongs to the area of comprehensive recovery and high value utilization of metallurgical waste residue. In this method, cyanide tailings, bentonite, calcium chloride, coal powder and albite are mixed by ball milling according to certain weight ratio to get a mixture. After drying and roasting twice, dust is collected from the roasted ash, the obtained polymetallic ash is collected and treated. The secondary calcined material is cooled to obtain ceramsite. The invention volatilizes and recovers the valuable metal in the roasting and sintering process of cyanide tailings and directly prepares the ceramsite through reasonable batching, which achieves the effect of recycling cyanide tailings and high-value utilization, can create good economic and environmental benefits, and has significant effect of energy saving and consumption reduction.