METHOD TO PROCESS METAL-CONTAINING SULPHIDE MINERAL RAW MATERIALS WITH EXTRACTION OF METALS Russian patent published in 2012 - IPC C22B3/08 C22B15/00 C22B19/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to the method for extraction of metals from metal-containing sulphide mineral raw materials. The method includes leaching with mixing of a sulphuric acid solution in presence of trivalent iron ions in at least two serially connected tubs, separation of leaching products into liquid and solid phases, iron oxidation in a liquid phase, return of the liquid phase after iron oxidation into leaching reservoirs, intermediate extraction of metals from liquid phases. At the same time the initial raw materials prior to leaching are exposed to preliminary acid treatment at PH=0.8-1.4, S:L=1:1. Leaching is carried out in two stages at the temperature of 75-95°, PH=1.0-1.2 and S:L=1:(3-6), concentration of trivalent iron ions of 30-45 g/l at each stage with separation of leaching products after each stage into liquid and solid phases and iron oxidation in a liquid phase after each stage and with extraction of metals at each stage from liquid phases after iron oxidation. To the first stage raw materials exposed to preliminary acid treatment are sent, and to the second stage - a solid phase is sent, produced after separation of leaching products at the first stage. The liquid phase, which was produced after oxidation of iron at the second stage, is returned to the last leaching reservoir of the same stage.

EFFECT: higher extent of extraction of all precious metals into a solution and reduction of process duration by 1,2-1,5 times.

4 ex, 1 dwg