One-pot synthesis of β-cyclodextrin magnetic carbon nanotube (β-CD@MMWCNT) for effective removal of phenol from oily wastewater

In this work, a novel composite material based on β-cyclodextrin magnetic carbon nanotube (β-CD@MMWCNT) was developed by a one-pot method (in situ co-precipitation) and applied as an adsorbent to remove phenol from oily wastewater. The basic structure, surface morphology, as well as physical and chemical properties of the composite material were analyzed. β-CD@MMWCNT was successfully prepared, confirmed by the attachment of Fe3O4and β-cyclodextrin particles on the surface. The adsorption behavior of phenol on β-CD@MMWCNT conformed to the Langmuir isotherm model and the pseudo-first-order kinetic model. The adsorption was a spontaneous endothermic process, and the adsorption capacity calculated by Langmuir model was 67.67 mg/g at 20 °C. Moreover, the adsorbent still maintained 85% of the adsorption capacity after 7 cycles. Specially, the adsorbent was used to adsorb phenol from simulated oily wastewater, and the removal rate of phenol reached 92.6%. And the possible adsorption mechanisms were also proposed by infrared and Raman spectroscopy. In summary, β-CD@MMWCNT can be used as a potential adsorbent to remove phenol from oily wastewater.