Journal of the Brazilian Chemical Society
On-line version ISSN 1678-4790
FLORES, Érico M. M. et al. Direct solid sampling by flame atomic absorption spectrometry: determination of manganese in coal samples. J. Braz. Chem. Soc. [online]. 2004, vol.15, n.2, pp. 199-204. ISSN 1678-4790. http://dx.doi.org/10.1590/S0103-50532004000200007.
A new device for the direct solid analysis by flame atomic absorption spectrometry was investigated as an alternative technique for the determination of trace elements in coal. The potential application of the proposed procedure for the determination of manganese was investigated. Ground coal test samples were weighed directly into polyethylene vials and carried as a dry aerosol to a slotted quartz vaporization cell placed between the flame burner and optical path. The transient signals obtained were totally integrated in 1 second. The effect of operating conditions on the analytical signal was investigated. Background signals were always low and a Mn characteristic mass of 1.9 ng was found. Results were considered satisfactory regarding to both accuracy (between 97.5 and 103.2%) and precision (RSD better than 6%). The proposed system is simple and can be easily adapted to any conventional atomic absorption spectrometers allowing the analysis of more than 80 test samples in an hour.
Keywords : flame atomic absorption spectrometry; direct solid sampling; manganese determination; coal analysis.