Reduction of gaseous phase interference in hydride generation using inductively coupled plasma atomic emission instead of flame heated quartz tube atomic absorption spectrometry: determination of selenium in nickel alloys and low-alloy steels

Selenium was determined in nickel and steel alloys by hydride generation in combination with both atomic absorption spectrometry (AAS)(heated quartz tube) and inductively coupled plasma atomic emission spectrometry (ICP-AES). A serious depression of the Se signal was observed when AAS was used for the determination, although the interference from Ni, Co, Cr, Fe and Cu was effectively masked with complexing agents. The depression was reduced when ICP-AES was used instead of AAS, indicating a gaseous phase interference. The interference may be caused by the presence of hydrides of Sn and As. For the determination of Se in nickel alloys and low-alloy steels, the detection limit was lowered by a factor 1.5–3 when ICP-AES was used instead of AAS. Several standard reference materials (nickel alloys and low-alloy steels) were analysed for Se.