Determination of Antimony in Lead-Antimony Alloys by Atomic Absorption Spectroscopy Using Indium as an Internal Standard

Abstract

A rapid, precise analytical method has been developed by the United States Department of the Interior, Bureau of Mines, for the determination of antimony in lead-antimony alloys. The alloy (0.10 to 30.0 wt.% Sb) is rapidly dissolved in a 10% volume nitric acid solution containing ∼5 g of tartaric acid. Antimony is determined by atomic absorption using indium as an internal standard. The relative standard deviation for this internal standard method, based on the analysis of three National Bureau of Standards (NBS) Standard Reference Materials, is approximately 0.50%; an improvement over conventional atomic absorption and a volumetric method by a factor of 5 to 8. The internal standard procedure gives values that are in better agreement with the NBS certified values than analyses using the alternative methods. Analytical time required is less than 30 min.