Synthesis of a New alpha-Dioxime Derivative and Its Application for Selective Homogeneous Liquid-Liquid Extraction of Cu(II) into a Microdroplet Followed by Direct GFAAS Determination

摘要

A fast and reliable method for the selective separation and preconcentration of Cu~(2+) ions using homogeneous liquid-liquid extraction was developed.A new alpha-dioxime derivative (2H-l,4-benzothioazine-2,3(4H)dione-dioxime,Dioxime I) was synthesized and investigated as a suitable selective complexing ligand for Cu~(2+) ions.Zonyl FSA (FSA) was applied as a phase-separator agent under the slightly acidic pH conditions.Under the optimal experimental conditions ([FSA] = 3.2% w/v,[THF] = 19.5% v/v,[Dioxime I] = 1.9 x 10~(-3) M,and pH = 4.7),10 mug of Cu~(2+) in 5.2 mL aqueous phase could be extracted quantitatively into 80 muL of the sedimented phase.The maximum concentration factor was 65-fold.The limit of detection of the proposed method was 0.005 ng mL~(-1).The reproducibility of the proposed method,on the 10 replicate measurements,was 1.3%.The influence of the pH,type and volume of the water-miscible organic solvent,concentration of FSA,concentration of the complexing ligand and the effect of different diverse ions on the extraction and determination of Cu~(2+) ions were investigated.The proposed method was applied to the extraction and determination of Cu~(2+) ion in different synthetic and natural water samples.