Simple Emulsification Microextraction for the Preconcentration of Palladium in Water Samples by Flame Atomic Absorption Spectrometry

Abstract

A simple and selective emulsification microextraction (EME) method in conjunction with flame atomic absorption spectrometry (FAAS) is reported for the preconcentration of palladium ions in aqueous solution. In this approach, N-(3-chloro-4-fluorophenyl)-N-phenylthiourea (CFPT) was synthesized for the first time for the complexation of metal ions including manganese, nickel, cadmium, cobalt, copper, gold, lead, palladium, iron, zinc, aluminum, and chromium and platinum with the microextraction method. The new CFPT ligand provided excellent selectivity toward Pd²⁺ ions in highly acidic conditions. The formation of a palladium hydrophobic compound with the new synthesized ligand was extracted into chloroform by shaking a model solution for a few seconds. The cloudy solution was centrifuged and the organic phase containing Pd²⁺ was diluted with nitric acid and transferred for the monitoring of the palladium absorbance by FAAS. Under the optimum conditions, the linearity (R² = 0.9986) was in the range from 10 to 1000 µg L⁻¹ and the limit of detection was 2.28 µg L⁻¹ for Pd²⁺. The developed EME-FAAS method was successfully applied for preconcentration and determination of Pd²⁺ in spiked samples such as well, stream, tap and sea water with good recoveries.

Keywords:

• Emulsification microextraction
• flame atomic absorption spectrometry (FAAS)
• palladium
• water samples

Conflict of interest

The authors declare no conflicts of interest.