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.

Process for recovering one or both of copper and silver from a sulphidic feed containing iron, arsenic, copper and silver by pressure oxidizing an aqueous feed slurry of the sulphidic feed in a pressure vessel to form a liquid phase containing free sulphuric acid and aqueous copper sulphate, and to precipitate arsenic as solid iron arsenic compounds. The process includes operating the pressure vessel at a sufficiently low solids content to maintain a free acid level below 30 g/L in the liquid phase, and providing sufficient heat to maintain a temperature in the pressure vessel above 200° C. Copper metal is recovered from the liquid phase and/or silver may be recovered from the solids by cyanide leaching without the need for a jarosite destruction step.

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 of recovering a metal from a low-grade ore which is subjected to cyanide leaching to produce a PLS which contains a metal cyanide which is removed from the PLS by ultrafiltration and nano-filtration, and then acidified and sulphidised to produce a metal sulphide from which the metal is extracted, and hydrogen cyanide which is recycled to the cyanide leaching step.

An oxidation step for sulfide and transition ores prior to CN leaching to recover 60 to 90 percent of metals from those ores. Use of tona, soda ash or carbonate source in treating sulfide and transition ores for CN leaching recovery of metals, including gold and silver. The oxidation of sulfide and transition ores in the presence of carbonate. Low moisture content in the heap, to enhance available oxygen, during the oxidation of sulfide and transition ores in the presence of carbonate.

An oxidation step for sulfide and transition ores prior to CN leaching to recover 60 to 90 percent of metals from those ores. Use of tona, soda ash or carbonate source in treating sulfide and transition ores for CN leaching recovery of metals, including gold and silver. The oxidation of sulfide and transition ores in the presence of carbonate. Low moisture content in the heap, to enhance available oxygen, during the oxidation of sulfide and transition ores in the presence of carbonate.

Methods of recovering metals from metal-bearing materials, and more particularly, methods for improving leaching efficiency in extraction processes by employing a surfactant composition in the extraction process, as well as slurries useful in the methods of recovering metals are provided.

Process for recovering one or both of copper and silver from a sulphidic feed containing iron, arsenic, copper and silver by pressure oxidizing an aqueous feed slurry of the sulphidic feed in a pressure vessel to form a liquid phase containing free sulphuric acid and aqueous copper sulphate, and to precipitate arsenic as solid iron arsenic compounds. The process includes operating the pressure vessel at a sufficiently low solids content to maintain a free acid level below 30 g/L in the liquid phase, and providing sufficient heat to maintain a temperature in the pressure vessel above 200 C. Copper metal is recovered from the liquid phase and/or silver may be recovered from the solids by cyanide leaching without the need for a jarosite destruction step.

An oxidation step for sulfide and transition ores prior to CN leaching to recover 60 to 90 percent of metals from those ores. Use of tona, soda ash or carbonate source in treating sulfide and transition ores for CN leaching recovery of metals, including gold and silver. The oxidation of sulfide and transition ores in the presence of carbonate. Low moisture content in the heap, to enhance available oxygen, during the oxidation of sulfide and transition ores in the presence of carbonate.

A method of recovering a metal from a low-grade ore which is subjected to cyanide leaching to produce a PLS which contains a metal cyanide which is removed from the PLS by ultrafiltration and nano-filtration, and then acidified and sulphidised to produce a metal sulphide from which the metal is extracted, and hydrogen cyanide which is recycled to the cyanide leaching step.