Interferences from nickel, lead, copper and silver and their elimination in the determination of mercury by cold vapour atomic-absorption spectrometry exemplified by fly ash assays

Abstract

The determination of mercury in the presence of metal ions (nickel, lead, copper and silver) was studied by cold vapour atomic-absorption spectrometry. The results unambiguously showed serious depressing interferences. However, by using EDTA as a complexing agent these interferences could be completely eliminated over a wide concentration range for nickel, lead and copper. For silver the interference could be only partly eliminated. Some fly ash samples were examined with and without EDTA addition.