Heterogeneous sono-Fenton catalytic degradation of bisphenol A by Fe3O4 magnetic nanoparticles under neutral condition

In this study, the Fe 3 O 4 magnetic nanoparticles (MNPs) were synthesized as heterogeneous catalysts to effectively degrade bisphenol A (BPA). The properties of the synthesized catalysts were characterized by Brunnaer–Emmett–Teller (BET), X-ray powder diffraction (XRD), X-ray photoelectron spectrometry (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. The results indicated that the Fe 3 O 4 MNPs appeared to be roughly spherical shapes and their average size was 10–20   nm. The catalytic capacity of MNPs in US   +   Fe 3 O 4   +   H 2 O 2 system with different pH conditions, H 2 O 2 concentrations and MNPs doses was investigated. It was found that the OH radicals were promptly generated due to the catalysis of the Fe 3 O 4 MNPs. BPA could be degraded within a wide pH range from 3 to 9, and the degradation efficiencies were remarkably enhanced by ultrasound. The apparent rate constants were 8.31   ×   10 −3 , 7.96   ×   10 −3 and 5.64   ×   10 −3   min −1 , respectively, when the pH values were 3, 7 and 9, respectively. The removal efficiencies of BPA were all over 95%. About half total organic carbon (TOC) in solution was eliminated under neutral condition by sono-Fenton process. Furthermore, the results of stability and reusability demonstrated that the Fe 3 O 4 MNPS were promising in the treatment of wastewater with refractory organics.