1978 Volume 27 Issue 11 Pages 692-696
An atomic absorption spectrophotometric method for sensitive and precice determination of antimony has been studied-being reduced to antimony-hydride (stibine) by sodium borohydride solution. The apparatus used for stibine generation consists of the reaction flask, magnetic stirrer, gas-reservoir and U-shaped drying tube. Stibine in the gas-reservoir is subsequently introduced into an argon supported hydrogen flame and determined by atomic absorption spectrophotometry. A flexible bag (TEDLAR bag) with two mouths for the gas-reservoir results in good reproducibility of stibine generation. Some suppressive effects by diverse ions are found to. be almost entirely eliminated, when the prereduction procedure using hydrazine sulfate was combined with sodium borohydride reduction. With the prereduction procedure are not found interferenes, up to 500-fold excess of Mn (VII), Cr(VI), Fe(III). A calibration curve obtained shows linear up to 1μg-Sb. The detection limit is 0.02μg-Sb and coefficient of variation in the determination of 1μg-Sb is 2.3 in 20 runs. This method was applied to the analysis of N. B. S. Standard Reference Material (SRM-1575) and water samples with satisfactory results.
