METHOD OF EXTRACTION OF OSMIUM AND RHENIUM FROM THE WASHING SULFURIC ACID Russian patent published in 2007 - IPC C01G47/00 C01G55/00 

FIELD: hydrometallurgy; methods of extraction of osmium and rhenium from the washing sulfuric acid.

SUBSTANCE: the invention is pertaining to the field of the hydrometallurgy of osmium and rhenium, in particular, to the methods of utilization of the osmium-and-rhenium-containing sulfuric acid formed in the system of the wet gas purification of the copper and nickel works and may be used for extraction and concentration of osmium and rhenium from the washing sulfuric acid. The method provides for treatment of the washing sulfuric acid solution having the concentration of H₂SO equal to 300-700 g/l with sodium or calcium hypochlorite up to provision of the value of the oxidized-reduced potential of 800-1000 mV for oxidization of osmium up to Os(VIII). Then the extraction of osmium and rhenium is sequentially exercised. At that in the beginning they extract osmium and then extract rhenium. The extraction of osmium is conducted using in the capacity of the extractant the diluent based on the saturated hydrocarbons, in particular, kerosene or the diesel fuel, at ratio of О:H = 1:5-25 with transfer of osmium into the extract, and rhenium - into the raffinate. The osmium-containing extract is subjected to the thermal treatment at 40-85°С, aged and filtered with production of the solid-phase osmium concentrate. Rhenium is extracted from the raffinate by the extractant containing 10-40 % of the tertiary amines at the ratio О:H=1:25-100. The technical result of the invention is the increased degree of extraction of osmium from the washing sulfuric acid with production of its individual concentrate at provision of the high degree of extraction of rhenium into the extract.

EFFECT: the invention ensures the increased degree of extraction of osmium from the washing sulfuric acid with production of its individual concentrate at provision of the high degree of extraction of rhenium into the extract.

6 cl, 4 ex