Study on Alkaline Hot-pressure Pre-oxidation for a Fine Disseminated Type refractory Gold Ore

The gold in an ore in Guizhou mainly exits in the form of parcel.The main gold-bearing minerals are pyrite,arsenopyrite,silicate and carbonate,the particle size of which is 1~5μm,existing in the state of ultramicroscopic and belonging to a fine disseminated type refractory gold ore containing sulfur and arsenic.To recover the gold in the ore,the oxidation pretreatment must be carried on in the alkaline medium to make sulfur,arsenic,antimony and iron oxidized into sulfate,arsenate,antimonite and hematite,finally leading to the damage of sulfide crystal so that the parceled gold is exposed and at last he cyanidation was used to recover.Experiment research was carried on through such factors affecting leaching as ore particle,alkaline dosage,leaching temperature,pulp density,oxygen partial pressure.leaching time and SAA dosage to select optimum condition.Finally,the leaching rate of gold reached 90.1%.