A new approach for fluorine determination by solid sampling graphite furnace molecular absorption spectrometry

• Published in: Spectrochimica acta. Part B: Atomic spectroscopy 2007-09, Vol.62 (9), p.918-923
• Main Authors: de Moraes Flores, Éder Lisandro, Barin, Juliano Smanioto, de Moraes Flores, Érico Marlon, Dressler, Valderi Luiz
• Format: Article
• Language: English
• Subjects: Alumina; Coal; Fluorine; Graphite furnace molecular absorption spectrometry; Solid sampling
• ISSN: 0584-8547; 1873-3565
• DOI: 10.1016/j.sab.2007.05.010

This work deals with the determination of fluorine by solid sampling graphite furnace molecular absorption spectrometry. The molecular absorbance of aluminum monofluoride (AlF), which is produced in the vapor phase in the presence of Al 3+, is measured at 227.5 nm, a non-resonant platinum line. A conventional graphite furnace program has been used with pyrolysis and vaporization temperatures of 800 and 2300 °C, respectively. Solutions of Ba 2+ and Al 3+ have been used to avoid fluorine losses during the pyrolysis stage and to produce AlF in the vaporization stage, respectively. Certified coal and alumina samples were analyzed using aqueous standards for calibration. The agreement between the found concentration and the certified value, or the value obtained by another method ranged from 92 to 105%, with a relative standard deviation less than 8.5%. The limit of detection and the characteristic mass was 0.17 μg g − 1 and 205 pg, respectively.