THE DETERMINATION OF TIN IN STEEL SAMPLES BY FLOW-INJECTION HYDRIDE GENERATION ATOMIC-ABSORPTION SPECTROSCOPY

Conditions were studied for the determination of Sn in steel samples using flow injection, hydride generation and atomic absorption spectroscopy. Interferences were found for the determination of Sn in steel samples and an investigation showed that the interferences occurred in the generation of the hydride, not in the atomization of the gaseous hydride. Conditions for the determination of Sn by flow injection hydride generation were improved by using integrated absorbance signals and by the addition of oxygen to the argon carrier gas stream. Typically, 500-mu-l of a 10-mu-g/l Sn standard provided an integrated absorbance signal greater than 0.5 A.s. The method provided a detection limit of about 0.05-mu-g/l in a 500-mu-l sample. The precision ranged from 1 to 3% RSD at higher concentration levels of Sn. The method of additions yielded accurate results for several steel standard reference materials in those situations where the use of the standard calibration procedure was inadequate.