Tube atomizers in thermospray flame furnace atomic absorption spectrometry: characterization using X-ray fluorescence, scanning electron microscopy and chemometrics

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.

Influence of TiO2 and ZrO2 nanoparticles deposition on a stainless steel furnace used for trace element determination by TS-FF-AAS

“…The interaction between the analyte and the coating lowered the atomization temperature, which increased the analytical signal as described for copper determination. 11 In order to quantify this process, another study should be conducted separately for each case and with an AAS method that allowed a better thermal control and homogeneity, for example EMFAAS. 5 The particular case of Cu was studied using the TiO 2 @steel furnace and bare steel furnace; results showed an improvement in the analytical response and sensitivity when using TiO 2 @steel furnace compared to bare steel furnace (see ESI †).…”

“…TiO 2 . 11 From this perspective, we employed stainless steel coated with TiO 2 or ZrO 2 nanoparticles (NPs) as a ame furnace.…”

Old and New Flavors of Flame (Furnace) Atomic Absorption Spectrometry

“…In order to bring information about variations in surfaces, shapes, and compositions of tube atomizers, Petrucelli et al [82] compared the performance of metal tube atomizers composed of Cr, Fe, Mo, Ni, Ti, and W and ceramic tubes before and after being used for determinations of Cd, Cu, Mn, Pb, and Zn by TS-FF-AAS in aqueous solutions, food and environmental samples. Nickel tube atomizers presented good performances for Cd, Cu, Pb, and Zn determinations and their lifetimes seemed to be long.…”

Relevant information of concomitants obtained from background signal using thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) and chemometric tools

“…More details about the TS-FF-AAS system can be found elsewhere. 14,15 X-ray spectroscopy (XRS) measurements were performed using a bench-top X-ray fluorescence equipment, Shimadzu EDX 700 (Kyoto, Japan), provided with a rhodium X-ray tube operated at a maximum voltage of 50 kV. The measurements were performed in 30 Pa vacuum, 25% detector dead time, 10 mm beam collimation and 100 s irradiation time.…”