Atomic absorption spectrometry of selenium in an argon-hydrogen flame after electrochemical preconcentration

Different methods of atomization of selenium from a platinum wire filament are described, including electrothermal heating of the filament and atomlzation in an argon-hydrogen flame. A combination of these approaches proved to give the best sensitivity and detection limit. The selenium was preconcentrated on the filament by electrolysis prior to the atomic absorption measurements to eliminate chemical interferences and improve the sensitivity of the method. The detection limit was 0.5 μg l^-1 for a 5-min electrolysis, and 0.2 μg l^-1 when the electrolysis time was 30 min.