Determination of Zn(II) in natural waters by ICP-OES with on-line preconcentration using a simple solid phase extraction system

LUIS A. ESCUDERO; LUIS D. MARTINEZ; JOSÉ A. SALONIA; JOSÉ A. GASQUEZ

MICROCHEMICAL JOURNAL

ELSEVIER SCIENCE BV

Año: 2010 vol. 95 p. 164 - 168

0026-265X

An on-line zinc preconcentration and determination system implemented with inductively coupled plasmaoptical emission spectrometry (ICP-OES) was developed. The zinc was precipitated and retained on aminicolumn filled with ethyl vinyl acetate (EVA) at pH 9.0, without using any complexing reagent. The zincions were eluted from the minicolumn with 10% (v/v) hydrochloric acid. Experimental conditions includingpH and sample loading and eluting variables were evaluated and established.An enrichment factor (EF) of 44 was obtained for Zn2+ with a preconcentration time of 120 s. Under theoptimal conditions, the value of the limit of detection (3σ) for the preconcentration of 10 mL of sample was0.08 μg L−1. The sampling frequency was about 24 h−1. The precision for six replicate determinations(repeatability conditions) at 50 μg L−1 Zn level was 3.94% relative deviation standard (RSD), calculated fromthe peak heights obtained. The methodology was successfully applied to the determination of zinc in tapwater samples and in a certified VKI reference material QC Metal LL1 DHI (Water & Environment) Denmark.