On-line adsorption/preconcentration using a knotted reactor for total Hg determination in drinking water by flow injection CV-AAS

WUILLOUD, JCA O ALTAMIRANO, JC; G. WUILLOUD, RODOLFO; GASQUEZ, J. A.; ANTONIO OLSINA, ROBERTO; DANTE MARTINEZ, LUIS

ATOMIC SPECTROSCOPY

Perkin Elmer

Lugar: NORWALK; Año: 2001 vol. 22 p. 398 - 404

0195-5373

The on-line coupling of a FI sorption preconcentration system with a knotted reactor to FI-CV-AAS increases the speed of the preconcentration and analysis processes as well as reducing sample consumption and contamination risks. The results of this work demonstratethe possibility of using S-Br-PADAP for preconcentration of mercury, since the Hg-S-Br-PADAP complex was effectively adsorbed on the inner surface of a KR made of PTFE. Fast and quantitative generation of cold vapor from the elution solution was obtained even in the presence of great excess of the complexing reagent. Coupling of the KR to the cold vapor generation system was possible without major modifications relative to conventional systems. The dead volume in the proposed separator was kept constant and to minimum value, which allowed increased reproducibility of the FI system and decreased the dispersion of the transient signals generated. The proposed system of preconcentration associated with mercury cold vapor generation allows mercury determinations in drinking water samples at levels as low as micro-g L-1 or less. The quantification of Hg in other samples such as river and seawater is a possibility provided the experimental conditions are adequately adjusted. The determination procedure shows good reproducibility and accuracy.