C22B11/02

METHOD FOR GOLD RECOVERY AND EXTRACTION FROM ELECTRONIC WASTE OR GOLD CONTAINING MINERALS, ORES AND SANDS

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 THE RECOVERY AND RECYCLING OF MATERIALS THAT CONSTITUTE SUPPORTED PALLADIUM MEMBRANES

A process for recycling and reusing supported Pd membranes includes the separation of the Pd (or Pd alloy) layer from the support by contacting the Pd membrane with hydrogen under pressure and at low temperature and then with a second gas that is different from hydrogen. The Pd layer separated from the support can then be treated to solubilize the Pd and, where appropriate, the alloy metal(s) to obtain salts that can be reused, for example in the preparation of new Pd membranes. The recovered supports are also reusable.

Process and device for burn-off of precious metal-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.

APPARATUS AND PROCESS FOR SEPARATING AND RECOVERING THE COMPONENTS OF AN ALLOY, PARTICULARLY A NOBLE ALLOY

An apparatus for separating and recovering the components of an alloy, particularly a noble alloy, including a high vacuum chamber housing at least one crucible for the alloy to be separated; at least one heating element arranged, during use, around the crucible; at least one condensation device, which faces, during use, an upper mouth of the crucible. The particularity of the present invention resides in that the condensation device includes at least one cold element and at least one deflector that is adapted to divert the flow of the aeriform substances derived from the melting and evaporation of the alloy toward the cold element. The invention also relates to a process for separating and recovering the components of an alloy, particularly a noble alloy.

Process for the recovery of precious metal from petrochemical process residues

A process for the recovery of precious metal (PM) from PM oil, the process including combustion of PM oil within a furnace, where the PM oil is burned in atomized form.

Method and apparatus for retrieving valuable metals step by step from waste printed circuit board particles

A method and apparatus for step-by-step retrieving valuable metals from waste printed circuit board particles. Many kinds of metals, most existing in form of elementary substance or alloy, are contained in the waste printed circuit boards. Molten metals are separated selectively by supergravity separation at different temperatures to achieve the step-by-step recovery. Tin-based alloys, lead-based alloy, zinc aluminum alloy, crude copper and precious-metal-enriched residues with different metal contents are separated out and collected on the condition of different temperatures (T=200300 C., 330430 C., 700900 C., 11001300 C.) and controlling the gravity coefficient (G=501000) and separation time (t=220 min) etc. Different metals or alloys can be separated quickly and efficiently and the residue concentration of precious metals can be obtained. The process is simple and low cost to provide an efficient way to recovery the enrichment of valuable metals from electronic wastes.

METHOD FOR SELECTIVE EXTRACTION OF GOLD BY NIACIN

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.

Jacketed rotary converter and PGM converting process
10648059 · 2020-05-12 · ·

Jacketed rotary converter. The converter includes an inclined pot mounted for rotation about a longitudinal axis, a refractory lining for holding a molten alloy pool, an opening in a top of the pot for introducing feed, a lance for injecting oxygen-containing gas, a heat transfer jacket for the pot adjacent the refractory lining, and a coolant system to circulate a heat transfer medium through the jacket to remove heat from the alloy pool in thermal communication with the refractory lining. Also disclosed is a PGM converting process using the jacketed rotary converter. The process can also include low-or no-flux converting; refractory protectant addition; slag separation; partial feed pre-oxidation; staged slagging; and/or smelting the slag in a secondary furnace with primary furnace slag.

Jacketed rotary converter and PGM converting process
10648059 · 2020-05-12 · ·

Jacketed rotary converter. The converter includes an inclined pot mounted for rotation about a longitudinal axis, a refractory lining for holding a molten alloy pool, an opening in a top of the pot for introducing feed, a lance for injecting oxygen-containing gas, a heat transfer jacket for the pot adjacent the refractory lining, and a coolant system to circulate a heat transfer medium through the jacket to remove heat from the alloy pool in thermal communication with the refractory lining. Also disclosed is a PGM converting process using the jacketed rotary converter. The process can also include low-or no-flux converting; refractory protectant addition; slag separation; partial feed pre-oxidation; staged slagging; and/or smelting the slag in a secondary furnace with primary furnace slag.

Centrifuge collection of minerals in flowing water
10603678 · 2020-03-31 ·

An apparatus for collection of heavier particles such as gold flowing in a river includes a support frame with legs for mounting in the river spaced from the bed with a series of drum mounted on the support frame one behind the other for rotation about an axis transverse to the river flow. The drums have a plurality of blades mounted so that flow of water in the river causes a rotation of the drum, a plurality of water entry openings and a plurality of discharge openings in the drum with the drum shaped such that rotation causes a centrifugal action such that the heavier particles remain within the drum against escape from the drum while lighter particles and water are discharged.