Preparation of Magnetic g-C3N4/Fe3O4 Composite and Its Application in the Separation of Catechol from Water

Catechol has strong toxicity and deformity as well as carcinogenicity, and it is difficult to degrade naturally. Therefore, it is of great practical significance to develop efficient adsorbents to separate catechol from water quickly and effectively. In this work, g-C3N4/Fe3O4 magnetic nanocomposites were prepared using g-C3N4 as the matrix by chemical co-precipitation, mixing with Fe2+ and Fe3+ solutions. Then, g-C3N4/Fe3O4 was used, for the first time, as an adsorbent to investigate the removal rate of catechol under different conditions by the magnetic field separation method. The adsorption parameters of the g-C3N4/Fe3O4 nanocomposite were evaluated by the Langmuir and Freundlich adsorption models. The results showed that the g-C3N4/Fe3O4 nanocomposite presented a two-step adsorption behavior and a considerably high adsorption capacity. The removal rate of catechol reached 70% at the dosage of 50 mg, adsorption time of 30 min, and pH value of 6. Five adsorption-desorption cycles demonstrated that the g-C3N4/Fe3O4 material had good stability and reusability.