Evaluation of electrothermal atomic absorption spectrometry for trace determination of Sb, As and Se in gasoline and kerosene using microemulsion sample introduction and two approaches for chemical modification

Studies aimed at the development of analytical methods based on electrothermal atomic absorption spectrometry for the determination of antimony, selenium and arsenic in gasoline and kerosene were performed. The goal was to develop sensitive methods that allow a simple calibration procedure to be used through direct correlation between analyte signals measured in the sample and signals from aqueous standards. This was possible by optimization of both the sample preparation procedure and furnace conditions. The platform atomization technique was used together with chemical modification (ruthenium permanent modifier or Pd/Mg nitrate chemical modifier). Better results were obtained when samples were introduced as microemulsions prepared with a surfactant (Triton X-100) rather than sample introduction as detergentless microemulsions (three component solution). Good sensitivity was achieved, which allowed the determination of analytes in gasoline and kerosene samples in the mg L range. Linear ranges up to three decades were observed for the analytical curves. Laboratory-prepared samples were analyzed with good precision and recovery.