The efficient removal of Cu(II) from aqueous solutions by Fe3O4@hexadecyl trimethoxysilane@chitosan composites

In this work, hexadecyl trimethoxysilane and chitosan grafted onto Fe3O4 (Fe3O4@C-16@CTS) was synthesized and characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, fourier transformed infrared spectroscopy, thermo gravimetric analysis, zeta potential and magnetic measurements. The Fe3O4@C-16@CTS composites were applied as adsorbents to remove Cu(II) from aqueous solutions and had a higher adsorption capacity than Fe3O4@C-16 due to the strong abilities of hydroxyl groups and amino in CTS to form complexes with metal ions. The adsorption isotherm was well described by the Langmuir model, with a maximum adsorption capacity of 261.78 mg/g at pH = 5.8 +/- 0.1 and T = 298 K. The Cu(II) absorbed on Fe3O4@C-16@CTS could be desorbed by HCl and remained a higher adsorption capacity even after 6 cycles. The results showed that the Fe3O4@C-16@CTS composites were potential materials for the removal of Cu( II) from aqueous solutions and could be separated by a simple magnetic separation method in wastewater treatment. (C) 2016 Elsevier B.V. All rights reserved.