Enhanced visible light assisted Fenton-like degradation of dye via metal-doped zinc ferrite nanosphere prepared from metal-rich industrial wastewater

In this work, a novel catalyst, metal-doped zinc ferrite nanosphere, was prepared from metal-rich industrial wastewater using two-step method for the removal of organic contaminants in the Vis-light/catalyst/H2O2 system. The physicochemical properties of the catalyst were well characterized by XRD, FESEM, TEM, XPS, and UV-vis. The results indicated that the catalyst exhibited better catalytic performance than pure ZnFe2O4 synthesized from chemical reagents, and Congo red (CR) decolorization efficiency reached 94.6% within 3 h. During the photo-Fenton process, center dot OH played an key role, which was generated through the photo-generated holes and the oxidation of H2O2 by metal ions (Fe3+ and Mn3+) on the surface of catalysts. Moreover, 75.5% of CR decolorization efficiency could be still retained at the third run. Thus, metal-doped ZnFe2O4 nanosphere prepared from metal-rich industrial wastewater is a promising photo-catalyst for the removal of organic chemicals in practical application of wastewater treatment. (C) 2018 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.