Determination of Trace Amounts of Beryllium(II) in Drinking Water and of Beryllium Vapor in Air by Graphite-Furnace Atomic Absorption Spectrophotometry Using Acetylacetone as a Chelating Agent

Abstract

A chelate of beryllium acetylacetonate, Be(acac)2, was formed from beryllium(II) (1.0 - 40.0 ng) in drinking water (100 ml) containing acetylacetone (0.2%(v/v), 7.0 - 14.0 ml) in ammonium acetate buffer (14 - 28 mmol) together with a slightly acidic solution (0.2%(v/v) of HCl, 3.0 ml) at pH 5.5. The Be(acac)2 chelate was preconcentrated on a Sep-Pak C18 cartridge and was eluted with methanol (2.00 ml). A portion (20 µl) was introduced into a graphite cuvette and was atomized according to a temperature program. The method detection limit (3σ) for beryllium(II) was 2.3 ng/l; the calibration graph was linear up to 400 ng/l. Accuracies of 97.0 - 101% were obtained when testing a quality control (QC) water sample (HPS #290608) and a synthetic natural water standard (Standard Reference Material 1643d) with a relative standard deviation (n=4) within 2.3%. The proposed method could be applied to the measurement of beryllium vapor in air with a detection limit of 0.23 ng.