METHOD OF DETERMINING PLATINUM IN ORE AND ORE CONCENTRATES BY STRIPPING VOLTAMMETRY ON SELECTIVE ELECTROOXIDATION PEAKS OF BISMUTH FROM INTERMETALLIC COMPOUND PtBi

摘要

FIELD: chemistry.SUBSTANCE: method of determining platinum in ore and ore concentrates by stripping voltammetry according to the invention involves transferring platinum (IV or II) from a sample into a solution and conducting voltammetric determination, wherein platinum is accumulated on glass-carbon or graphite electrodes impregnated with polyethylene and paraffin in a stirred solution in the presence of bismuth ions for 60-120 s, followed by recording of anode peaks for selective electrooxidation of bismuth (III) from intermetallic compound PtBiwith potential sweep rate of 60-100 mV/s, electrolysis potential from -0.30 to -1.1V on the following backgrounds: 1-0.5 M HNOor 1-0.5 M HCl. Concentration of platinum (IV or II) ions is determined from the value of area under the voltage versus current curves at potential ranging from 0.15 V to 0.45 V relative a saturated silver chloride electrode using a certified mixture addition technique, in order to reduce the lower limit of the determined content and widen the range of determined content of platinum (IV or II) by determining platinum from selective electrooxidation peaks of bismuth from an intermetallic compound (IMC) PtBi.EFFECT: reducing the lower limit of the determined content and widening the range of determined content of platinum when determining platinum from selective electrooxidation peaks of bismuth from an intermetallic compound PtBi.1 dwg, 2 tbl