Surface β-Cyclodextrin Polymer Coated Fe3O4 Magnetic Nanoparticles: Synthesis, Characterization and Application on Efficient Adsorption of Malachite Green

Surface β-cyclodextrin polymer coated Fe3O4 magnetic nanoparticles (NPs) were prepared by anchoring pyromellitic dianhydride derivate-b-cyclodextrin polymer (b-CD-P) onto the surface of Fe3O4 magnetic NPs, which is generated in situ through a co-precipitation method. The transmission electron microscopy (TEM) result indicates that Fe3O4@β-CD-P NPs have an effective average size of 15 ± 2 nm. The surface coated layer β-CD-P was confirmed by Fourier-Transformed Infrared Spectroscopy, and the amount of which was determined to be 138.2 mg g-1 by thermogravimetric analysis. To explore the potential application of such nanocomposites for organic pollutants adsorption, malachite green (MG), a typical cancer-causing water pollutant was evaluated by spectrophotometric method. It was finally learnt that, the adsorption rate of MG by Fe3O4@β-CD-P NPs follows pseudo-second-order kinetics with adsorption isotherm fitted by the Langmuir isotherm model well. The maximum adsorption capacity was measured to be 88.49 mg g-1 at 25 °C. Additionally, a good recyclability of the Fe3O4@β-CD-P was observed over four usage cycles, with slight decrease of adsorption capability.