Fabrication of PbO2/PVDF/CC Composite and Employment for the Removal of Methyl Orange

Abstract

The in situ electrochemical oxidation process has received considerable attention for the removal of dye molecules and ammonium from textile dyeing and finishing wastewater. Nevertheless, the cost and durability of the catalytic anode have seriously limited industrial applications of this technique. In this work, the lab-based waste polyvinylidene fluoride membrane was employed to fabricate a novel lead dioxide/polyvinylidene fluoride/carbon cloth composite (PbO2/PVDF/CC) via integrated surface coating and electrodeposition processes. The influences of operating parameters (pH, Cl− concentration, current density, and initial concentration of pollutant) on the oxidation efficiency of PbO2/PVDF/CC were evaluated. Under optimal conditions, this composite achieves a 100% decolorization of methyl orange (MO), 99.48% removal of ammonium, and 94.46% conversion for ammonium-based nitrogen to N2, as well as an 82.55% removal of chemical oxygen demand (COD). At the coexistent condition of ammonium and MO, MO decolorization, ammonium, and COD removals still remain around 100%, 99.43%, and 77.33%, respectively. It can be assigned to the synergistic oxidation effect of hydroxyl radical and chloride species for MO and the chlorine oxidation action for ammonium. Based on the determination of various intermediates, MO is finally mineralized to CO2 and H2O, and ammonium is mainly converted to N2. The PbO2/PVDF/CC composite exhibits excellent stability and safety.

Characterization of a Ti/SnO2-Sb/Fe-PVP-PbO2 Electrode Deposited from Methanesulfonate Bath and Application in Electrocatalytic Degradation of MO

“…Noteworthy is the fact that the polycrystalline form of lead dioxide is usually not completely stoichiometric, and Pb (IV) state with strong oxidization in the films can be converted to Pb (II) state, improving the conductivity of PbO 2 electrode. 45,46 For both Ti/SnO 2 -Sb/Fe-PbO 2 and Ti/SnO 2 -Sb/Fe-PVP-PbO 2 electrodes, the high-resolution XP spectra of Fe 2p are presented in Fig. 5.…”

“…According to the reported studies, •OH radicals plays the most important role in the electrochemical destruction of organic pollutants. 46,52,55 •OH radicals attack the methyl group of MO anion, leading to the formation of demethylated MO. Meanwhile, •OH radicals target the N=N structure in the MO anion to destruct the azo structure, contributing to the discoloration of MO.…”