Alternative Leaching Reagents for Gold

  • J. C. Yannopoulos


Sodium cyanide has been the preponderant leaching reagent for gold due to its excellent extractions from a great variety of ores and its low cost. Although cyanide is poisonous, it has safe industrial and environmental records at the high pH range required in cyanide leaching. In addition, the low concentrations of cyanide used in gold milling and heap leaching are quickly degradable. Although cyanide is a powerful lixiviant for gold and silver, it is not selective and forms complex compounds with a multitude of metal ions and minerals. (See the list of cyanicides in Figure 9-1.)


Precious Metal Cyanide Solution Gold Extraction Gold Dissolution Heap Leaching 
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© Van Nostrand Reinhold 1991

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  • J. C. Yannopoulos

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