One-step solvothermal synthesis of magnetic Fe₃O₄–graphite composite for Fenton-like degradation of levofloxacin

ABSTRACT

A novel Fe₃O₄–graphite composite was prepared, characterized, and investigated as a heterogeneous Fenton-like catalyst for the degradation of levofloxacin (LEV) in an aqueous solution. The results revealed that the Fe₃O₄–graphite composite exhibited excellent properties for the degradation and mineralization of LEV, achieving a nearly complete degradation of 50 mg L⁻¹ LEV in 15 min and 48% of total organic carbon removal in 60 min under optimal conditions. A large electronic conjugation structure exists in graphite, which may lead to the fast production of •OH radical species because of the easy reduction of Fe(III) to Fe(II). In addition, we observed that the graphite can degrade LEV in the presence of H₂O₂. Therefore, the synergistic results of the graphite structure and Fe₃O₄ magnetic nanoparticles (MNPs) may contribute to the high catalytic activity of the Fe₃O₄–graphite composite. Compared with pure Fe₃O₄ MNPs, lesser iron leaching of the Fe₃O₄–graphite composite was observed during the degradation of LEV. The degradation efficiency of LEV remained approximately 80% at the fifth recycling run, which indicates that the Fe₃O₄–graphite composite has potential applications in water treatment for removing organic pollutants.

KEYWORDS:

• Fe₃O₄–graphite composite
• Fenton-like degradation
• Levofloxacin
• solvothermal synthesis

Funding

This study was supported by the Development Program of the Ministry of Science and Technology of Jilin Province, China (Grant no. 20150204070GX).