title: [Investigation of stages of chemical leaching and biooxidation during the extraction of gold from sulfide concentrates].
abstract: We examined the chemical leaching and biooxidation stages in a two-stage biooxidation process of an auriferous sulfide concentrate containing pyrrhotite, arsenopyrite and pyrite. Chemical leaching of the concentrate (slurry density at 200 g/L) by ferric sulfate biosolvent (initial concentration at 35.6 g/L), which was obtained by microbial oxidation of ferrous sulfate for 2 hours at 70°C at pH 1.4, was allowed to oxidize 20.4% ofarsenopyrite and 52.1% of sulfur. The most effective biooxidation of chemically leached concentrate was observed at 45°C in the presence of yeast extract. Oxidation of the sulfide concentrate in a two-step process proceeded more efficiently than in one-step. In a two-step mode, gold extraction from the precipitate was 10% higher and the content of elemental sulfur was two times lower than in a one-step process.
authors.forename: M I
authors.initials: MI
authors.lastname: Murav'ev
authors.forename: N V
authors.initials: NV
authors.lastname: Fomchenko
authors.forename: T V
authors.initials: TV
authors.lastname: Kondrat'eva
mesh_terms: D005290:Ferric Compounds / Q000737:chemistry*; D006046:Gold / Q000737:chemistry / Q000302:isolation & purification*; D006801:Humans; D007501:Iron / Q000737:chemistry; D010084:Oxidation-Reduction; D013440:Sulfides / Q000737:chemistry*
chemical_list: D005290:Ferric Compounds; D013440:Sulfides; C011342:pyrite; C024823:ferric sulfate; D006046:Gold; D007501:Iron