Adsorptive stripping voltammetry is proposed for the determination of boron at the low μgg
-1 level in iron and steel. Beryllon III was used as a complexing agent for boron(III). Optimum conditions for a complex formation of boron(III)-Beryllon III complex were as follows: 0.06 M nitrate-0.04 M sulfate supporting electrolyte at pH 4.5; 1.0×10
-5 M Beryllon III; 24 h complexation time. The complex was accumulated on a hanging mercury drop electrode at-0.35 V for 60 s under stirring, and subsequently was cathodically stripped to -0.8 V at a scan rate of 10mVs
-1 by using a differential pulse mode. The interference of iron(III) was eliminated by complexing it with metaphosphoric acid. The cathodic stripping resulted in only a single well-defined peak around -0.5 V. The influence of foreign elements on the determination was evaluated. The calibration graph (peak height
vs. boron(III) concentration) in the presence of 1 mg mL
-1 iron(III) was linear over the concentration range of 1-25 ng mL
-1 (correlation coefficient >0.999), with a relative standard deviation (
n=4) of 2.6% at 10 ng mL
-1. The minimum limit of determination was 1μgg
-1 of boron in iron and steel. The proposed method could be applied to the determination of trace boron in iron and steel with good precision and accuracy.
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