Conference Proceedings
World Gold '97 Conference, Singapore, September 1997
Conference Proceedings
World Gold '97 Conference, Singapore, September 1997
An Investigation of the Selective Leaching of Gold Over Copper Using Ammoniacal Cyanide
Copper minerals are often associated with gold ores. These create processing problems since cyanide solutions are not selective for gold alone. Copper minerals are also leached by cyanide, and typically each one per cent of `reactive' copper in the ore consumes about 30 kg t 1 cyanide. Once in solution, copper cyanide species create further processing problems as they adsorb onto carbon along with the dicyanoaurate ion. These problems make conventional cyanidation of gold ore uneconomic if the ore contains too much copper. As a result, methods of economically processing gold-copper ores are becoming of increasing importance._x000D_
One of the more promising methods of treating these ores is by selective leaching of the gold by an ammoniacal cyanide solution, a method first described by Hunt in 1901. This method is already in commercial use in Mauritania, treating copper/gold tailings. In general terms, the addition of I - 2 g U1 ammonia to a standard cyanide leach solution causes a significant increase in gold extraction and decrease in copper extraction. However, early testwork on this system has concluded that the optimal leach conditions are critically dependent on ore composition, and the mechanism is not well understood, making predictions of best conditions impossible.
One of the more promising methods of treating these ores is by selective leaching of the gold by an ammoniacal cyanide solution, a method first described by Hunt in 1901. This method is already in commercial use in Mauritania, treating copper/gold tailings. In general terms, the addition of I - 2 g U1 ammonia to a standard cyanide leach solution causes a significant increase in gold extraction and decrease in copper extraction. However, early testwork on this system has concluded that the optimal leach conditions are critically dependent on ore composition, and the mechanism is not well understood, making predictions of best conditions impossible.
Contributor(s):
K Drok, I Ritchie
-
An Investigation of the Selective Leaching of Gold Over Copper Using Ammoniacal CyanidePDFThis product is exclusive to Digital library subscription
-
An Investigation of the Selective Leaching of Gold Over Copper Using Ammoniacal CyanidePDFNormal price $22.00Member price from $0.00
Fees above are GST inclusive
PD Hours
Approved activity
- Published: 1997
- PDF Size: 0.193 Mb.
- Unique ID: P199702004