Preparation of modified multiwalled carbon nanotubes (l-Arg-CS/MWCNTs-COOH/Fe3O4) as sorbent for dispersive solid phase extraction of Cu(II), Pb(II) and Cd(II) in wastewater samples

Abstract

A new modified multiwalled carbon nanotube (l-Arg-CS/MWCNTs-COOH/Fe3O4) as sorbent of dispersive solid phase extraction (DSPE) was synthesized for preconcentration and determination of Cu (II), Pb (II), and Cd (II) in wastewater samples. The successful formation of sorbent was characterized by FTIR (Fourier transform infrared) spectroscopy, SEM (Scanning electron microscope), and XRD (X-ray diffraction). Batch experiments such as solution pH, amount of adsorbent, extraction time, type and volume rate of eluent and etc were achieved to study the sorption process. At optimized conditions the adsorbent shows good recovery with 4mL ethylene diamine tetra acetic acid) EDTA( as eluent. Good fitting of sorption kinetics by pseudo-second-order model was obtained. Limits of detection were found in the range of 0.10-0.12 μg L−1 for metal ions, the liner range was 5-1000 μg L−1 for Cd(II) and 10-1000 μg L−1 for Cu(II) and Pb(II) and the preconcentration factor 60, 65 and 55 for Cu(II), Pb(II) and Cd(II), respectively. The relative standard deviation was in the range of 1.5-2.3 %. Results showed that the new magnetic nanosorbent was an efficient DSPE adsorbent for preconcentration and determination of Cu (II), Pb (II), and Cd (II) in wastewater samples.