METHOD FOR BACTERIAL LEACHING OF RARE-EARTH AND NOBLE METALS FROM ASH Russian patent published in 2016 - IPC C22B7/04 C22B59/00 C22B11/00 C22B3/18 

FIELD: metallurgy.

SUBSTANCE: invention relates to method of extracting rare-earth and noble metals from ash. Method involves mixing with leaching solutions, accumulation of biomass of microorganisms of genus Acidithiobacillales, bacterial leaching of rare-earth and noble metals. Then obtained suspension is separated into sediment and clarified liquid and is separated from last rare-earth and precious metals. Prior to extraction of metals in clarified liquid concentrate is added active sludge, used for 1 to 600 minutes after its production, in volume ratio of clarified liquid concentrate of active sludge accordingly 1:(0.1-1.5). Concentrate before adding in clarified fluid is aerated. Concentrate of active sludge is obtained by flotation suspension active sludge formed during biological purification of waste water with air flow from 1 to 15% of active sludge suspension flow rate and size of air bubbles from 0.01 to 0.9 mm.

EFFECT: invention technical result is high efficiency of extracting rare-earth and noble metals from ash.

5 cl, 3 ex