Spectrochimica Acta Part B: Atomic Spectroscopy

Autor: Borges, Aline Rocha, Becker, Emilene M., François, Luciane L., Jesus, Alexandre de, Valea, Maria Goreti R., Welz, Bernhard, Dessuy, Morgana B., Andrade, Jailson Bittencourt de
Jazyk: angličtina
Rok vydání: 2014
Předmět:
Zdroj: Repositório Institucional da UFBA
Universidade Federal da Bahia (UFBA)
instacron:UFBA
DOI: 10.1016/j.sab.2014.08.040
Popis: Texto completo: acesso restrito. p.213–219 Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2015-03-25T15:20:22Z No. of bitstreams: 1 Aline R. Borges.pdf: 1115957 bytes, checksum: 6273d8dd7c441c7cbeb33d018c620cc1 (MD5) Made available in DSpace on 2015-03-25T15:20:22Z (GMT). No. of bitstreams: 1 Aline R. Borges.pdf: 1115957 bytes, checksum: 6273d8dd7c441c7cbeb33d018c620cc1 (MD5) Previous issue date: 2014 In the present work, spectral interferences on the determination of lead in fertilizer and limestone samples were investigated using high-resolution continuum source graphite furnace atomic absorption spectrometry at the main analytical lines: 217.001 and 283.306 nm. For these investigations, samples were introduced into the furnace as slurry together with a mixture of Pd and Mg as chemical modifier. Spectral interferences were observed for some samples at both analytical lines. In order to verify whether a wet digestion procedure would avoid these interferences, a reference method for wet digestion of fertilizers was employed as an alternative sample preparation procedure. However, the same interferences were also observed in the digested samples. In order to identify and eliminate the fine-structured background using a least-squares background correction, reference spectra were generated using the combination of different species. The use of the latter technique allowed the elimination of spectral interferences for most of the investigated samples, making possible the determination of lead in fertilizer and limestone samples free of interferences. The best results were found using a reference spectrum of NH4H2PO4 at 217.001 nm, and a mixture of H2SO4 + Ca and HNO3 + Ca at the 283.306 nm line. The accuracy of the method was evaluated using a certified reference material “Trace Elements in Multi-Nutrient Fertilizer”. Similar results were obtained using line source graphite furnace atomic absorption spectrometry with Zeeman-effect background correction, indicating that the latter technique was also capable to correct the spectral interferences, at least in part.
Databáze: OpenAIRE