Determination of Ni(II) in metal alloys by spectrophotometry UV-Vis using dopasemiquinone

Barreto, Wagner José, Barreto, Sonia Regina Giancoli, Scarminio, Ieda Spacino, Ishikawa, Dílson Norio, Soares, Miriam de Fátima, Proença, Marcus Vinícius Brás de

Determination of Ni(II) in metal alloys by spectrophotometry UV-Vis using dopasemiquinone

AUTOR(ES)

Barreto, Wagner José, Barreto, Sonia Regina Giancoli, Scarminio, Ieda Spacino, Ishikawa, Dílson Norio, Soares, Miriam de Fátima, Proença, Marcus Vinícius Brás de

FONTE

Química Nova

DATA DE PUBLICAÇÃO

2010

RESUMO

A spectrophotometric method was proposed for Ni(II) determination in alloys using a dopa-semiquinone (L-1) to form [Ni(II)(L1-)3]1-, ε = 9.3 x 10³ L mol-1 cm-1. The optimal conditions for the determination were: wavelength 590 nm, temperature 25 °C, reaction time 45 min and pH 7.5. The Beer's law was obeyed for nickel from 3.33 x 10-5 to 1.78 x 10-4 mol L-1. The method was applied to complex samples, such as inox, nickel-titanium and cobalt-chromium alloys. A study of the potential interferents revealed that Mn was the major interferent. The limit of detection and quantification were 2.88 x 10-5 mol L-1 and 3.06 x 10-5 mol L-1, respectively.