Resumo

AGUILAR, J. C.; RODRIGUEZ DE SAN MIGUEL, E.  e  DE GYVES, J.. Adsorptive stripping voltammetry of In(III) in the presence of pyrogallol red in chloride-acetate media. Rev. Soc. Quím. Méx [online]. 2001, vol.45, n.1, pp.17-20. ISSN 0583-7693.

In this work optimal working conditions were established for the adsorptive stripping analysis of In(III) on a hanging mercury drop electrode with pyrogallol red as the preconcentration agent in chloride-acetate media using staircase and square-wave voltammetry (SCV and SWV). The influence of ligand adsorption and concentration, supporting electrolyte and pH on the voltammetric response was studied. From these results the stoichiometric ratio of the complex and the value of its corresponding formation constant were determined. Under optimized chemical and instrumental conditions limits of detection (3σ) of 7.0 × 10⁻⁹ M and 4.0 × 10⁻⁹ M were obtained for SCV and SWV, respectively, using a deposition time of 90 s. The relative standard deviations (n = 21) were 3.3 and 4.8 % for a 1.5 × 10⁻⁷ M In(III) concentration. The results of an analysis carried out for indium present in aluminum alloys were in good agreement with those obtained using ICP-AES as an alternative method.

Palavras-chave : Adsorptive stripping voltammetry; In(III); pyrogallol red.