Determination of cadmium in aqueous samples by vapour generation with sodium tetraethylborate(III) reagent

Abstract

A volatile cadmium compound can be generated from aqueous solutions containing Cd²⁺ at trace levels, by reaction with sodium tetraethylborate(III) at room temperature. Preliminary experiments failed to identify this compound but it appears to be sufficiently stable to be used for analytical purposes. A detection limit for the compound of 0.2 ng ml^–1(3σ of a blank determination, 1-ml sample volume) can be achieved using non-dispersive atomic fluorescence spectrometry with argon-hydrogen mini-flame atomisation whereas with conventional atomic absorption spectrometric measurements in a flame-heated silica tube the detection limit is 1 ng ml^–1(3δ of the base-line noise, 1-ml sample volume).