SiO₂ Stabilized Magnetic Nanoparticles as a Highly Effective Catalyst for the Degradation of Basic Fuchsin in Industrial Dye Wastewaters.

Abstract

Catalytic degradation of organic pollutants by nanomaterials is an effective way for environmental remediation. The Fenton reaction involving H2O2 oxidation catalysed by Fe3+ is an advisable way for wastewater degradation. Herein, Fe3O4/SiO2 core-shell nanoparticles were prepared as catalyst by coprecipitation and sol-gel methods, and this catalyst is used for degradation of fuchsin in wastewater by H2O2. The Fenton reaction between H2O2 and Fe3O4 is proposed to explain the catalytic performance. The coating of SiO2 on Fe3O4 nanoparticles could dramatically stabilize the Fe3O4 in aqueous solution and prevent their oxidation. More importantly, the magnetic property of Fe3O4 nanoparticles endows them with good recyclability. Thus, due to the outstanding catalytic results, almost 100% removal degradation was achieved within 5 min over a wide pH value range at room temperature, which is better than that without catalysts. Temperature is a positive factor for improving the degradation rate, but room temperature is selected as the best temperature for economic and energy savings reasons, because more than 98% of fuchsins can still be degraded at room temperature. Moreover, these Fe3O4/SiO2 core-shell nanoparticles exhibit excellent magnetic recyclability and stable properties after repeated utilization. Therefore, these as-presented Fe3O4/SiO2 core-shell nanoparticles with low-cost and high performance are expected to be applied in practical industry wastewater degradation.