Physical description
Wooden model of a cyanide plant. A cyanide plant was used for dissolving gold from finely divided ores by means of dilute solutions of sodium or potassium cyanides. The model has five metal bins; there is some rust on the bins and scorch mark on the wooden base.
Subjects
- mining,
- equipment,
- cyanide plant,
- gold cyanidation (also known as the cyanide process or the macarthur-forrest process) is a hydrometallurgical technique for extracting gold from low-grade ore by converting the gold to a water-soluble coordination complex. it is the most commonly used leaching process for gold extraction. the ore is comminuted using grinding machinery. depending on the ore,
- it is sometimes further concentrated by froth flotation or by centrifugal (gravity) concentration. water is added to produce a slurry or pulp. the basic ore slurry can be combined with a solution of sodium cyanide or potassium cyanide,
- however many operations utilize calcium cyanide,
- which is more cost effective. to prevent the creation of toxic hydrogen cyanide during processing,
- slaked lime (calcium hydroxide) or soda (sodium hydroxide) is added to the extracting solution to ensure that the acidity during cyanidation is maintained over ph 10.5 - strongly basic. lead nitrate can improve gold leaching speed and quantity recovered,
- particularly in processing partially oxidized ores.
