Fast and effective removal of cadmium ion from water using chitosan encapsulated magnetic Fe3O4 nanoparticles

A novel CS2-modified chitosan encapsulated magnetic Fe3O4 nanoparticles (CMCS@Fe3O4) was prepared for the removal of Cd(II) from aqueous solution. The adsorption behavior of the CMCS@Fe3O4 toward Cd(II) was studied using batch method. The CMCS@Fe3O4 showed a rapid process and a superior adsorption capacity for Cd(II). The adsorption kinetics followed the pseudo-second-order and the equilibrium data were well described by the Langmuir isotherm for the CMCS@Fe3O4. The maximum adsorption capacity of CMCS@Fe3O4 for Cd(II) was 200mgg(-1) from the Langmuir isotherm. Based on Fourier transform infrared spectroscopy analysis, the -NH2 and -SH groups on the CMCS@Fe3O4 mainly participated in the Cd(II) adsorption process. In addition, the common coexisting ions had a negligible impact on Cd(II) adsorption on the CMCS@Fe3O4. Overall, the results reported herein indicated that the CMCS@Fe3O4 is very attractive and implies a potential of practical application for the removal of toxic heavy metals.