No abstract

This work describes some complementary strategies for characterization and performance evaluation of tube atomizers used in thermospray flame furnace atomic absorption spectrometry. Metal tubes composed of Cr, Fe, Mo, Ni, Ti and W and ceramic tubes were characterized before and after being used for determinations of Cd, Cu, Mn, Pb and Zn in aqueous solutions, food and environmental samples. The best performances were observed for Ni-99% and Ti-99% atomizers. Ti and Ni atomizer lifetimes were around 5 and at least 88 hours, respectively. Titanium oxide (TiO 2) formation on the external surfaces of Ti tubes is a clear indication of its short lifetime. This observation was confirmed by X-ray fluorescence analyses and histograms of images obtained by scanning electron microscopy. Nickel tube atomizers presented small morphological distinctions when comparing new and used tubes, without affecting their analytical performances.