METHOD FOR OSMIUM DETERMINATION Russian patent published in 1995 - IPC

FIELD: analysis of materials. SUBSTANCE: method for osmium determination includes introduction into reaction of mixture of acetic, boric and phosphoric acids, and oxidation and reduction reaction is conducted at the following concentration of components: potassium periodate (4,4-4,8)·10^-4 M, sodium arsenite (0,8-1,2)·10^-3; sulfuric acid (1,9-2,1)·10^-2 M; and acetic, boric and phosphoric acids in the amount of (1,2-0,6)·10^-2 M each. Introduced into mixing vessel are: sodium arsenite solution in sulfuric acid into the I-st compartment; potassium periodate solution and analyzed solution of osmium into the 2-nd compartment; mixture of acids (acetic, boric and phosphoric) into the 3-rd compartment with water added to obtain volume of 25 ml. All compounds are mixed and induction period duration is measured from the moment of mixing up to formation of iodine, which is fixed amperometrically. Osmium concentration is determined by graduating graph constructed in coordinates: reverse duration of induction period osmium concentration. EFFECT: higher efficiency. 2 tbl