Ultrasonic Fenton-like catalytic degradation of bisphenol A by ferroferric oxide (Fe₃O₄) nanoparticles prepared from steel pickling waste liquor

In this study, Fe₃O₄ NPs (named as Fe₃O₄ NPs-PO) were prepared by steel pickling waste liquor to reduce the cost of preparation, and were compared with those obtained by the common co-precipitation method (named as Fe₃O₄ NPs-CP) which prepared from chemical reagent using BET, XRD, XPS, TEM and SEM techniques. The results indicated that Fe₃O₄ NPs-PO nanoparticles mainly existed in the form of Fe₃O₄and appeared to be roughly spherical in shape with a size range of 20-50 nm. The heterogeneous Fenton-like catalytic capacity of Fe₃O₄ NPs-PO in US+ Fe₃O₄+H₂O₂ system was comprehensively investigated. BPA could be degraded within a wide pH range of 7-10. The removal efficiencies of BPA were close to 100% and about 45% total organic carbon (TOC) in solution was eliminated at the optimized conditions. It was found that •OH radicals which mainly caused the degradation of BPA were promptly generated due to the catalysis of the Fe₃O₄ NPs-PO. Furthermore, the comparative study of catalytic activity, stability and reusability between Fe₃O₄ NPs-PO and Fe₃O₄ NPs-CP showed that the two catalysts both remained good activity after several reaction cycles and no significant change in composition and structure was observed, the loss of catalyst was negligible, which demonstrated that Fe₃O₄ NPs-PO were promising in ultrasonic Fenton-like process to treat refractory organics. Copyright © 2014 Elsevier Inc. All rights reserved.