Simultaneous analysis of trace concentrations of lead and arsenic by energy-dispersive x-ray fluorescence spectrometry

Abstract

A method for the analysis of trace concentrations of lead by Energy-Dispersive x-Ray Fluorescence spectrometry when arsenic is also present in the sample is described. To apply the method, the Pb_Lβ-line, emitted from the sample to be analyzed, must be available and it cannot interfere with x-ray peaks from other constituents in the sample. An additional reference sample containing lead and no arsenic is required. The intensity ratio (Pb_Lα/Pb_Lβ) is used for correction using a reference which is arsenic free. By applying the emission-transmission method (Giauque et al., 1973) the corrected intensities of Pb_Lα- and As_Kα-peaks are calculated for samples of unknown composition. Based on the corrected intensities the concentrations of Pb and As are determined. To verify the method the IAEA reference material, Marine Sediment SD-M-2/TM, was analyzed and the results are presented here.