ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Voltammetric Determination of Antimony in Natural Waters

D. Rúriková and M. Počuchová

Department of Analytical Chemistry, Faculty of Natural Sciences, Comenius University, SK-842 15 Bratislava

Abstract: A procedure for determining Sb(III) and total dissolved Sb in natural waters using differential pulse voltammetry (DPV) in enriched solution with hanging mercury drop electrode in the presence of catechol is described. The DPV involves three steps: electrochemical reduction to elemental antimony at -1.0 V, reoxidation to Sb(III), and accumulation in the form of catechol complex after fast potential change to -0.1 V and cathodic scan from -0.1 V to -1.0 V. The Sb(III) may be determined with a detection limit 0.1 mu g dm(-3) and a linear response in the range 0.5 to 8 μg dm^-3 for a 480 s deposition. This voltammetric technique responds to Sb(III) only. Therefore Sb(V) must be converted to Sb(III) with chemical reduction prior to its determination. The precision and accuracy of the pretreatment procedure and DPV technique were evaluated by analyzing synthetic water spiked with known amounts of Sb(III) and Sb(V). The relative standard deviations ranged from 1.3 to 9.8 % and the recoveries were > 90 % for both Sb species in most cases. Finally, the developed method was successfully applied to the analysis of Sb in natural waters.

Full paper in Portable Document Format: 511a15.pdf

Chemical Papers 51 (1) 15–21 (1997)