Determination of tellurium in lead and lead alloy using flow injection-hydride generation atomic absorption spectrometry

Abstract

A method based on flow injection-hydride generation atomic absorption spectrometry (FI-HG AAS) for the determination of trace amount of Te in lead and lead alloy is described. A flow injection system (FI) and related analytical parameters as well as Te determination and interference caused by Pb, Bi and Ag on Te were investigated. The Pb interference could be overcome by using a small sample volume, while the Bi interference could be overcome by thiourea. However, it was not possible to minimise the interference caused by Ag on Te. The optimised conditions for Te determination in the analysed samples were: 6 mol l −1 HCl as sample carrier solution, 0.75% (m/v) sodium tetrahydroborate as Te reductant, 40 μl of sample solution, and 200 ml min −1 Ar flow rate as carrier gas. The limit of quantification (LOQ) was 1.0 μg g −1 Te (using 250 mg of sample in 50 ml final solution), the limit of detection (LOD) was 2.5 μg l −1 and the relative standard deviation (RSD) was 6% for five consecutive measurements of sample solution. The standard addition calibration method was used. Relatively high sample throughput (ca. 45 sample runs can be performed in a working hour), reduced sample manipulation since matrix separation is not necessary, and minor waste generation are the main advantages of the proposed method for Te determination by FI-HG AAS.