Novel determination of copper(II) in natural waters by solid-phase extraction (SPE) flow-injection (FI) flame atomic absorption spectrometry (FAAS)

Abstract

A novel functionalized silica gel with the Schiff base of N-{[3-[(3-aminopropyl)amino]propyl}-2-hydroxy-benzaldimine was fabricated and utilized for flow-injection (FI) solid-phase extraction (SPE) of Cu(II) ions with flame atomic absorption spectrometric determination in environmental water samples. The practical factors on the FI-SPE of Cu(II) ions, including flow rates and volumes of sample and eluent solutions, eluent type and concentration, sample pH, and matrix ions, were studied. The maximum absorbance of Cu(II) ions was obtained using sample solutions at pH 7.0 at 5.0 mL min−1 with elution by 500 µL of 1.0 M HCl. Batch adsorption capacity of the functionalized silica gel for Cu(II) ions was 24.7 ± 0.3 mg g−1. The developed FI-SPE method was successfully validated by the determination of Cu(II) in water certified reference materials, including water-trace elements (NWTM-15.2) and Ontario Lake water (NWTMDA-54.4). Cu(II) levels in environmental samples such as tap, river, and sea water were successfully determined using the reported FI-SPE method.