Use of 2-(tert-butoxy)-N-(3-carbamothioylphenyl)acetamide and graphene oxide for separation and preconcentration of Fe(III), Ni(II), Cu(II) and Zn(II) ions in different samples

Abstract A simple and selective method using a column packed with graphene oxide (GO) as a solid phase extractant has been developed for the multi-element preconcentration of Fe(III), Ni(II), Cu(II) and Zn(II) ions prior to flame atomic absorption spectrometric determinations. The method is based on the sorption of mentioned ions on synthesized GO using 2-( tert -butoxy)- N -(3-carbamothioylphenyl)acetamide as a chelating agent. Several parameters on the extraction and complex formation were optimized. Under the optimized conditions (pH 6, flow rate 9 mL/min), metal ions were retained on the column, then quantitatively eluted by HNO 3 solution (5 mL, 3.0 mol/L). The preconcentration factor was calculated as 250. The detection limits for the analyte ions of interest were found in the range of 0.11 ng/mL (Ni 2+ ) to 0.63 ng/mL (Cu 2+ ). The column packed with GO was adequate for metal ions separation in matrixes containing alkali, alkaline earth, transition and heavy metal ions.