PROCEDURE FOR EXTRACTION OF RHENIUM FROM METAL WASTE OF NICKEL CONTAINING HEAT RESISTANT ALLOYS Russian patent published in 2011 - IPC C22B61/00 C22B23/00 C22B3/08 

FIELD: metallurgy.

SUBSTANCE: procedure consists in processing wastes with sulphuric acid at raised temperature, in supplying hydrogen peroxide, in introducing rhenium, nickel and cobalt into leaching solution and in concentrating tungsten, niobium and tantalum in insoluble residue. Further, solution is separated from insoluble residue; extraction of rhenium from solution is leached with secondary aliphatic alcohol. Extract is washed and rhenium is re-extracted with leaching solution upon extraction. Hydrogen peroxide is supplied after main part of nickel and cobalt have passed into solution at maintaining redox potential in interval of 0.50-0.75 V relative to a saturated chlorine-silver electrode, while extraction of rhenium, extract washing and rhenium re-extraction are carried out on 2-5 steps.

EFFECT: increased extraction of rhenium at reduced consumption of oxidant, increased safety of procedure due to separated in time operations followed with release of hydrogen and oxygen.

6 cl, 4 ex