extraction of gold by cyanide process patent

Cyanide Process - Gold Cyanidation Process Gold Leaching or

Cyanide process is also called as Macarthur-forest Process. It is the process of extracting gold or silver from the ores by dissolving in a dilute solution of potassium cyanide or sodium cyanide. This process was introduced in the year 1887 by the Scottish chemists naming Robert W. Forrest John S. MacArthur and William Forrest.

CA2245101C - Gold extraction process - Google Patents

There is described a process for the extraction of gold from a graphite or carbonaceous ore wherein the ore is ground in general mill solution with kerosene to 85% - 350 mesh and then the gold is extracted in a CIP carbon in pulp CIL carbon in leach or CIC carbon in column gold milling operation.

New Eco-Friendly Non-Cyanide Based Alternative for Gold

The patent-pending EnviroLeach process is safe eco-friendly and provides faster leach kinetics than cyanide on most ores concentrates and tailings. extraction with the use of cyanide. The

US4421724A - Extraction method for - Google Patents

Cyanic extraction of precious metal from comminuted refractory precious metal ore as well as refractory precious metal concentrates and tailings from such ore is effected with rapidity and high yield by agitationally treating the refractory material with an aerated alkaline solution containing a high concentration of water soluble cyanide and a low concentration of chemical oxidizer such as

US5667557A - Hydrometallurgical extraction - Google Patents

A hydrometallurgical process for treating copper feed materials containing gold and/or silver by simultaneously leaching copper gold and/or silver into an aqueous cyanide solution recovering copper in metallic form by electrowinning and regenerating cyanide ions is provided wherein high current efficiencies are achieved at high current densities and at low copper concentrations.