Determination of Chromium, Copper and Lead in River Water by Graphite-Furnace Atomic Absorption Spectrometry after Coprecipitation with Terbium Hydroxide

抄録

Coprecipitation with terbium hydroxide quantitatively recovered trace amounts of chromium(III), copper(II) and lead(II) at pH 8.4 - 10.8, 8.0 - 11.5 and 8.7 - 11.5, respectively. The precipitate was dissolved in 0.85 mol dm^-3 nitric acid, and the analytes were determined by graphite-furnace atomic absorption spectrometry (GF-AAS). The presence of terbium (up to 7 g dm^-3) did not interfere with the determination. The detection limits were 0.3 µg dm^-3 for chromium, 0.4 µg dm^-3 for copper and 0.5 µg dm^-3 for lead, when the analytes in 200 cm³ of the sample solution were concentrated into 10 cm³. The ions added to river or seawater were quantitatively recovered. Chromium and copper in a contaminated river water were successfully determined.