A process for recovery of one or more elements, selected from precious metals and chalcophile metals, as herein defined, from materials containing precious and/or chalcophile metal/s, said process including: (i) contacting the material with an alkaline solution containing a lixiviant comprising an amino acid, or derivative thereof, and an alkali stable transition metal complex in order to form a leachate containing the precious metal and/or chalcophile metal; and (ii) recovering the precious metal and/or chalcophile metal from the leachate.

Provided is a process for recovery of gold from gold-bearing raw materials comprising (a) leaching said gold-bearing raw material in a chloride containing leaching solution containing a total concentration of less than 120 g/L of halide ions, whereby the total concentration of chloride ions is less than 120 g/L of to dissolve gold and to obtain a leach solution comprising gold in solution; and simultaneously contacting the leach solution comprising gold in solution with a re-sorptive material to obtain a leach solution comprising gold-bearing re-sorptive material; and (b) recovering gold and optionally silver from the said gold-bearing re-sorptive material.

Described is a method of recovering a metal from a substrate having a metal sulphide, metal oxide, or combination thereof, by contacting the substrate with an aqueous oxidant to oxidize the metal sulphide to elemental sulphur and oxidized metal or convert the complex metal oxide to a metal salt, contacting the oxidized metal or simple metal oxide with ammonium hydroxide to form soluble a ammine complex of the metal to obtain a leachate and residual solids; separating the leachate from the residual solids; and recovering the metal.

Contemplated is a sensor system for use with a measuring device. The measuring device being of the type adapted to measure the volume of a desired solid component in a sample volume of a solid-liquid slurry obtained from either a carbon-in-pulp or carbon-in-leach process. The solid-liquid slurry comprises granular carbon particles, ore pulp, and water. The carbon-in-pulp or carbon-in-leach process includes at least one retention tank. The measurement device including: a receptacle for receiving the sample volume of the slurry; a screen provided in the receptacle for separating out the desired solid component from a remainder of the slurry. The solid component is retained in the receptacle to form a bed therein and the remainder is exhausted from the receptacle. The sensor system measures in either the retained solid component, or the exhausted remainder, or both one of: pH; dissolved oxygen; pulp density or carbon content.

The disclosure relates to pre-treatment of precious metal-bearing oxide ores, prior to precious metal leaching by thiosulfate. The process comprises mixing oxide ore in oxygenated water in the presence of a carbon-based material (e.g., activated carbon or other type of carbon). The carbon-based material can be separated from the ore slurry, and, the gold is thereafter leached by a thiosulfate lixiviant.

The disclosure provides a method of producing a platinum colloid comprising reducing platinum ions by the use of a platinum ion solution, water, a nonionic surfactant, a pH adjusting agent, and a reducing agent, wherein the platinum ion solution contains platinum at a concentration of 20 w/v %, the nonionic surfactant is polysorbate 80, the pH adjusting agent is an alkaline metal salt, the reducing agent is a lower alcohol, the volume of the water is from 600 to 660 times that of the platinum ion solution, the volume of the nonionic surfactant is from 0.20 to 0.30 times that of the platinum ion solution, the volume of the pH adjusting agent as a 5 w/v % aqueous solution is from 10 to 30 times that of the platinum ion solution, and the volume of the reducing agent is from 27 to 37 times that of the platinum ion solution,
as well as the platinum colloid produced by the method.

The present disclosure is a method and system for the processing of ore and ore tailings to recover metals, minerals and rare earth elements, and more particularly to a method and system for treating the ore and ore tailings using a closed loop chlorine gas oxidant treatment system using an electrochemical cell and the co-addition of an additional oxidizer such as chloric acid to enhance the dissolution of the metals from the ore which is then further processed to separate and recover the metals.

A hydrometallurgical process for the treatment of polymetallic ores and sulphide concentrates of copper and zinc, and by-products of lead and zinc from smelting plants, treated independently and/or as mixtures thereof, which contain relevant amounts of lead, copper, zinc, iron, gold and silver, such as the matte-speiss mixture of lead foundries, and copper cements from the purification processes of electrolytic zinc plants. The process allows the recovery of metallic copper, zinc, copper as copper and zinc basic salts, which may be hydroxides, carbonates, hidroxysulphates or mixtures thereof; the production of stable arsenic residues; and the effective and efficient recovery of Pb, Au and Ag as a concentrate of lead sulphide and/or lead, Au, and Ag sulphate.

The disclosure relates to pre-treatment of precious metal-bearing oxide ores, prior to precious metal leaching by thiosulfate. The process comprises mixing oxide ore in oxygenated water in the presence of a carbon-based material (e.g., activated carbon or other type of carbon). The carbon-based material can be separated from the ore slurry, and, the gold is thereafter leached by a thiosulfate lixiviant.

A method for recovering at least one precious metal from an aqueous solution containing the metal and particularly to recovery of silver and optionally one or more other precious metals from overflow of a sedimentation unit such as a thickener, a clarifier or a pond includes subjecting the aqueous solution to a micro and/or nanobubble flotation, wherein the pH of the aqueous solution is at most 1.5.