ANALYTICA CHIMICA ACTA, cilt.575, sa.1, ss.133-137, 2006 (SCI-Expanded)
The present paper proposes a pre-concentration procedure for determination of lead and iron in several samples by flame atomic absorption spectrometry. In it, lead(II) and iron(III) ions are coprecipitated using the violuric acid-copper(H) system as collector. Afterwards, the precipitate is dissolved with 1 M HNO3 solution and the metal ions are determined. The optimization step was performed using factorial design involving the variables: pH, violuric acid mass (VA) and copper concentration (Cu).