Abstract
Humic acid (HA)-coated Fe3O4 (Fe3O4/HA) superparamagnetic nanoparticles were synthesized by a chemical co-precipitation method with cheap and environmental friendly iron salts and HA. The as-synthesized samples were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR) and vibrating sample magnetometer (VSM). The Fe3O4/HA nanoparticles showed faster adsorption rate and higher removal capacity of cationic organic dye Methylene blue (MB) in neutral water. Moreover, the MB desorption could be easily completed. And the reused performance of Fe3O4/HA nanoparticles was also excellent.