| 摘要 |
Provided is a method for leaching gold from gold ore containing pyrite. Said method for leaching gold includes a pretreatment step that includes a step (1) in which gold ore containing pyrite is prepared, and a step (2) in which the gold ore is heated to 450°C or higher, and the pyrite in the gold ore is thermally decomposed into iron(II) sulfide and elemental sulfur. Said method for leaching gold further includes a leaching step that includes: a step (3) in which the pretreated gold ore is brought into contact with an iron leaching solution containing any one or more substances selected from sulfuric acid, hydrochloric acid, and Fe3+ aqueous salt solution to leach out iron components in the ore, and then solid-liquid separation is conducted on the iron leachate and residue; and a step (4) in which the residue obtained in step (3) is brought into contact with a gold leaching solution, which contains halide ions, copper ions and iron ions, while being supplied with an oxidant, to leach out gold components in the residue. Said method for leaching gold further includes an iron leaching solution regeneration step (5) in which the iron content is precipitated in an iron oxyhydroxide form, and removed from the iron leachate obtained in step (3). |
