Preconcentration of hydrogen selenide using hydride generation and purge-and-trap collection for the determination of selenium in water samples by atomic absorption spectrometry

ABSTRACT

Gaseous hydrogen selenide (H₂Se) generated by the addition of sodium tetrahydroborate (NaBH₄) into an acidic aqueous sample was collected using an aqueous ammonia solution. The selenium (Se) concentration was determined using graphite furnace atomic absorption spectrometry (AAS). Several experimental conditions, such as the type of the collection solution, volume of NaBH₄ and hydrochloric acid, and collection time, were optimized. In addition, the effect of coexisting ions was quantitatively evaluated and eliminated. The limit of detection for Se in a standard water sample was 1.3 ng/mL. The additional recovery of spiked Se in tap water and river water samples ranged from 98 ± 2.4 to 100 ± 2.2%. The proposed method facilitates simple and sensitive analysis for Se in water samples without H₂Se gas generator for AAS.

KEYWORDS:

• Selenium
• hydrogen selenide
• atomic adsorption spectrometry
• purge-and-trap

Disclosure statement

No potential conflict of interest was reported by the author(s).