Synthesis of magnetic ferrite/carbon nano sphere composites (MFe₂O₄/CNS, M = Mn, Ni, Zn) for Rhodamine B degradation by catalyzing persulfate

Nano magnetic particles immobilized on the surface of carbon spheres (MFe₂O₄/CNS, M = Mn, Ni, Zn) composites have been obtained through a facile and environmental friendly solvothermal method. The measurement results of MFe₂O₄/CNS clarified the successful preparation of MFe₂O₄/CNS and characterization of composites. Meanwhile, the activation performance of MFe₂O₄/CNS was also measured through catalyzing persulfate (PS) for degrading Rhodamine B. Results showed that the catalytic performance of MFe₂O₄/CNS for PS activation was much stronger than that of pure CNS, and the catalytic ability of MFe₂O₄/CNS was MnFe₂O₄/CNS > NiFe₂O₄/CNS > ZnFe₂O₄/CNS. The influence factors of Rhodamine B degradation were also investigated. When the optimum conditions were conducted, with PS 5 × 10^–3 M, MnFe₂O₄/CNS 0.5 g/L, initial pH 6.0, and 60 °C, 98.4% Rhodamine B degradation was obtained within 70 min. Finally, the recycle of MnFe₂O₄/CNS was carried out for four times, which demonstrated the favorable retrievability and reusability of MnFe₂O₄/CNS. The experiments also proved that the synthesized MnFe₂O₄/CNS was a potentially useful catalyst for contaminants degradation in water/wastewater treatment.