A comparative study by volatile covalent hydride atomic absorption spectrophotometry of interferences for arsenic(III)/(V) and selenium(IV) with direct atomization in an air-acetylene flame and in a silica tube

Abstract

This paper studies the effect of 26 interfering species on the signal of arsenic as AsH 3 generated from its two oxidation states and on the signal of selenium as H 2Se, using the following atomization systems: silica tube heated externally by an air-acetylene flame, and direct atomization in an air-acetylene flame without carrier gas. In general, most of the species inhibit the arsenic signal, the interference being greater when atomizing in the flame than when atomizing in a silica tube, and even for Fe 3+, Ca 2+, Cu 2+, Cr 3+, V 5+, and Mo 6+ the effect is positive in this case. For selenium, the highest interferences arise from the other elements which form volatile covalent hydrides and from Ni 2+, Cu 2+, Co 2+, and V 5+.