RECOVERY OF GOLD FROM AURIFEROUS REFRACTORY IRON- CONTAINING SULPHIDIC MATERIAL

摘要

A process for recovering gold from refractory auriferous iron containing sulphidic material which comprises treating an aqueous slurry of the material in a pressure oxidation step at a temperature in the range of from about 135 to about 250.degree.C under a total pressure of from about 500 to about 5000 kPa to oxidize sulphide sulphur to sulphate form and release gold from a refractory state. The pH of the resultant oxidized slurry is adjusted to a value suitable for cyanidation. The pH adjusted slurry is subjected to a cyanidation step in which gold is dissolved in a cyanide solution. The cyanided slurry is diluted to a pulp density in the range of from about 2 to about 10% solids by weight. The diluted slurry is subjected to a liquid-solids separation step to produce a gold containing solution and a relatively high pulp density gold-containing slurry, and gold from the gold-containing solution and from the high pulp density gold-containing slurry is separately recovered.