Determination of Arsenic in Lead-based Alloy Using Hydride Generation Atomic Fluorescence Spectrometry

A simple method based on HG-AFS for the determination of As in lead-based alloys was developed. Interferences caused by co-existing elements were investigated and minimized successfully, and conditions for the hydride generation technique and instrumental parameters were also optimized. KBH4 concentration was fixed at 1.0% (w/v). Optimized HCl concentrations in the sample and in the carrier solution were 10% (v/v) and 5% (v/v), respectively. Experiments showed that no interference caused by Cu was observed when thiourea existed and interferences caused by Sb, Sn and Bi could be eliminated by absorbing their corresponding hydrides using 0.5% (w/v) KMnO4 solution online. Feasibility of this method was demonstrated by the determination of two certified lead-based alloys, and the results obtained by standard addition agreed well with certified values. The method detection limit estimated was approximately 0.17 μg l−1 and RSD was 1.45% for 11 consecutive determinations of the 40 μg l−1 As standard solution.