Efficient rhodamine B degradation using electro-fenton process with PbO2-coated titanium as the anode

Abstract

To replace the high cost Pt anode, Ti based PbO2 electrode (PbO2-Ti) and Ti based SnO2 doped with Sb electrode (SnO2/Sb-Ti) were fabricated and compared for treating 0.1 mM Rhodamine B (RhB) in Electro-Fenton (EF) process. Scanning electron microscopy, energy dispersive X-ray, X-ray diffraction spectrometry were carried out to study the surface morphology, element composition, and substance composition of the anodes (PbO2-Ti and SnO2/Sb-Ti). Linear Sweep Voltammetry, cyclic voltammetry, Tafel, and electrochemical impedance spectroscopy were conducted to examine the electrochemical properties of the anodes (Pt, PbO2-Ti, SnO2/Sb-Ti, and Ti). These assessments showed that PbO2-Ti had the best performance. Then, the influence of varied parameters (pH, types of anodes, current density, and electrolyte) were explored. Almost complete decolorization (99.01%) was reached at pH 3, current density 50 A/m2, 0.05 M Na2SO4 using PbO2-Ti as the anode after 20 min electrolysis. Under these conditions, 90.48% of total organic carbon was removed after 180 min. Finally, the durability of PbO2-Ti was evaluated via accelerated service life test and exhibited long service lifetime (∼4000 h). © 2018 American Institute of Chemical Engineers Environ Prog, 38: 189–197, 2019.