Determination of Trace Aluminum in Iron and Steel Samples by Graphite Furnace Atomic Absorption Spectrometry

Direct determination procedure of trace aluminum in iron and steel samples by graphite furnace atomic absorption spectrometry (GF-AAS) has been studied. A rapid analytical method to determine acid-soluble Al and total Al separately was established. Atomization of the analyte was carried out by the stabilized temperature platform furnace (STPF) method using a L’vov platform. Sample solutions were prepared by dissolving iron and steel samples in nitric acid. In the analysis of acid-soluble Al, the supernatant liquid of the centrifuged sample solution was used. While, in the analysis of total Al, the sample solution was fed onto the graphite furnace by means of an ultrasonic slurry sampler. The detection limit (3σ of blank value) was 0.08 ppm when the weight of the sample was 1 g. The use of centrifugal separation and ultrasonic dispersion as the method of pretreatment reduced the blank value due to contamination from the environment and shortened analytical time significantly. The identical working curve for calibration is usable to determine both acid-soluble Al and total Al. The standard samples are not required.