Selective separation and preconcentration of copper (II) in environmental samples by the solid phase extraction on multi-walled carbon nanotubes

A solid phase extraction method for selective separation-preconcentration of copper (II) on multi-walled carbon nanotubes (MWNTs) prior to its flame atomic absorption spectrometric determinations has been investigated. The adsorption was achieved quantitatively on MWNTs column at pH 7.0, then the retained Cu(II) contents on the column were quantitatively eluted with 2 M HNO3. The effects of analytical parameters including pH of the solution, eluent type, sample volume, flow rates of eluent, matrix ions etc. were investigated for optimization of the presented procedure. The preconcentration factor was 60. The detection limit for copper (II) was found as 1.46 μg/L. The method was applied to the determination of copper in environmental samples and reproducible results were obtained.