Highly selective cloud point extraction and preconcentration of trace amounts of silver in water samples using synthesized Schiff’s base followed by flame atomic absorption spectrometric determination

Abstract

A simple and useful method employing cloud point extraction is proposed for the preconcentration and separation of silver in water samples. The silver cation reacts with bis(2-mercaptoanil) acetylacetone (BMAA) at pH 6. The resulting compound is subsequently entrapped in the Triton X-114 micelles. After optimization of the complexation and extraction conditions, a preconcentration factor of 50 was obtained (volume of initial sample was 10 mL). As an analytical example, trace amounts of Ag were determined, after preconcentration, in a complex aqueous matrix such as seawater using flame atomic absorption spectrometry. The calibration curve was linear in the range 2–200 ng/mL and the limit of detection was 0.43 ng/mL. The relative standard deviation was lower than 2.4%.