Degradation of Bisphnol a under Visible Light with Activation of Peroxydisulfate by Using Zinc Ferrite from Spent Alkaline Zn-Mn Batteries

Abstract

The photocatalyst zinc ferrite (ZnFe2O4) was synthesized via sol-gel method by using waste alkaline Zn-Mn batteries as raw materials. The nanoparticles were examined by X-ray diffraction (XRD) for crystalline phase identification, and the visible light response ability was identified by diffused reflectance spectrum (UV-Vis DRS). The prepared ZnFe2O4 was employed as catalyst to degrade bisphnol A (BPA) under visible light (λ≥400 nm) with activation of peroxydisulfate (PDS). The effects of PDS concentration, ZnFe2O4 dosage, initial pH on BPA degradation were investigated. Results indicate that nearly complete removal of BPA (0.1 mmol/L) could be achieved at natural pH within 120 min by using 5 mmol/L PDS and 0.5 g/L ZnFe2O4, which proved the catalyst a good applicability in handling organic pollution. The results of quenching experiments indicate that photogenerated hole played an important role in BPA removal. Photoluminescence spectroscopy combined with photoelectrochemical tests show the good performance of catalyst. This work also provides an alternative way for the reutilization of spent alkaline Zn-Mn batteries.

Keywords: ZnFe2O4, peroxydisulfate, photocatalysis, bisphnol A