Selective Determination of Trace-Bismuth by Extraction-Differential Pulse Polarography in Non-Aqueous Media

The voltammetric characteristics of bismuth(III)-oxinate in chloroform at the mercury electrode were investigated and a quasi-reversible behavior for Bi(III) oxinate reduction was confirmed. Preceded by the extraction of Bi(III) oxinate in chloroform, differential pulse polarography was developed in the extracts for determination of the trace-bismuth. The linear range of the calibration graph and the detection limit respectively were: 1´10-6 -5´10-5 and 4.7´10-7 M of Bi(III). Suitability and accuracy of the proposed method for determination of trace-bismuth was established by the analysis of a metallic aluminum sample.