Structural selective regulation of Fe3O4@C composite as adsorbent for removing different organic pollutants

Many wastewater treatment methods have been developed because large amounts of organic pollutants (OPs) entered into the water bodies and adsorption is one of the classic and important technologies. Recently, magnetic adsorbents have garnered extensive attention due to the high efficiency and distinctive recyclability. The control of their structures and surface properties is crucial. Here, the magnetite@carbon (Fe3O4@C) composite was prepared by coupling microreactor and pyrolysis reactor. The structures and surface properties of the Fe3O4@C were effectively adjusted by changing the pyrolysis temperature and Na2CO3 concentration. The Fe3O4@C composite prepared at 800 degrees C of pyrolysis temperature with 1 mol<middle dot>L-1 of Na2CO3 concentration has lipophilicity and the highest adsorption capacity of 92# gasoline among those adsorbents, which is as high as 7.6 g<middle dot>g(-1). The Fe3O4@C synthesized at 500 degrees C with 1 mol<middle dot>L-1 of Na2CO3 concentration has hydrophilicity and the highest adsorption capacity of Rhodamine B and Methyl Blue. The saturated adsorption capacities are about 166 and 301 mg<middle dot>g(-1), respectively. Fe3O4@C can be easily separated from wastewater and simply regenerated with less capacity loss after five cycles. The results show that the Fe3O4@C prepared by this method could be suitable for the removal of different OPs by adjusting the preparation conditions.