Performance of bimetallic nanoscale zero-valent iron particles for removal of oxytetracycline

In this study, bimetallic nanoscale zero-valent iron particles (nZVI), including copper/ nanoscale zero-valent iron particles (Cu/nZVI) and nickel/nanoscale zero-valent iron particles (Ni/nZVI), were synthesized by one-step liquid-phase reduction and applied for oxytetracycline (OTC) removal. The effects of contact time and initial pH on the removal efficiency were studied. The as-prepared nanoscale particles were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). Finally, the degradation mechanisms of OTC utilizing the as-prepared nanoparticles were investigated by using X-ray photoelectron spectroscopy (XPS) and mass spectrometry (MS). Cu/nZVI presented remarkable ability for OTC degradation and removed 71.44% of OTC (100 mg/L) in 4 hr, while only 62.34% and 31.05% of OTCwas degraded by Ni/nZVI and nZVI respectively. XPS and MS analysis suggested that OTC was broken down to formsmall molecules by center dot OH radicals generated fromthe corrosion of Fe-0. Cu/nZVI and Ni/nZVI have been proved to have potential asmaterials for application in OTC removal because of their significant degradation ability toward OTC. (c) 2017 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.