Preconcentration and atomic absorption determination of copper traces in waters by on-line adsorption-elution on an activated carbon minicolumn.

ABSTRACT

A continuous preconcentration method for the determination of trace copper in waters was developed. Ammonium pyrrolidinedithiocarbamate is used to form a chelate which is adsorbed on an activated carbon minicolumn and desorbed with 200 mul of methyl isobutyl ketone. The organic extract is driven by a water stream to an atomic absorption spectrometer. By using a time-based technique equivalent to from 1.5 to 4.5 ml of sample, preconcentration factors between 35 and 100, respectively, are achieved. The flow system is quite simple and rapid, and provides highly precise results (RSD 1.8-3.5%). The results obtained in the determination of copper in waters show the usefulness of the proposed method.