A comparative study on electrochemical oxidation of bisphenol A by boron-doped diamond anode and modified SnO2-Sb anodes: Influencing parameters and reaction pathways. Issue 3 (September 2016)

• Record Type: Journal Article
• Authors: Wu, Weiyi; Huang, Zhao-Hong; Lim, Teik-Thye
• Is Part Of: Journal of environmental chemical engineering. Volume 4:Issue 3(2016:Sep.)
• Page Start: 2807
• Page End: 2815
• Publication Date: 2016-09
• Subjects: Boron doped diamond -- Antimony doped tin dioxide -- Supporting electrolyte -- Byproducts -- Pathway; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2016.05.034
• Languages: English
• ISSNs: 2213-2929

Abstract

Highlights: Electrochemical oxidation of BPA was studied with BDD and modified SnO2 -Sb anodes. The influences of solution pH and type of supporting electrolyte were investigated. The modified SnO2 -Sb anodes are more suitable for treating wastewater containing Cl −1 . Reaction pathways are proposed by determining aromatic and aliphatic acid intermediates. Abstract: In this study, electrochemical oxidation of bisphenol A (BPA) was investigated using BDD anode and two types of modified SnO2 -Sb anodes, TiO2 -NTs/SnO2 -Sb-PTFE and Ti/SnO2 -Sb/SnO2 -Sb-CNT. The influences of solution pH (3, 7 and 11) and the type of supporting electrolyte (0.05 M Na2 SO4 and 0.1 M NaCl) on the electrocatalytic activity of the three anodes were investigated. The anodes exhibited remarkably different behavior for BPA oxidation, due to their different surface morphology, oxygen evolution potential and ability in the hydroxyl radical generation. Both BDD and the modified SnO2 -Sb anodes could degraded BPA effectively in 0.05 M Na2 SO4 at pH 3 and 7. However, in 0.1 M NaCl, TiO2 -NTs/SnO2 -Sb-PTFE and Ti/SnO2 -Sb/SnO2 -Sb-CNT showed better electrocatalytic activity for BPA oxidation than BDD with less Cl loss and ClO3 − generation. On the contrary, a considerable amount of chlorinated intermediates and polymer byproducts were observed with BDD, resulting in its ineffective TOC removal (46.8%). It indicates that the modified SnO2 -Sb anodes are more environmentally benign for the treatment of wastewater containing chloride ion. LC–MS/MS and ion chromatography revealed the aromatic intermediates and aliphatic acids produced during BPA oxidation. Finally, the reaction pathways of BPA oxidation in Na2 SO4 and NaCl supporting electrolytes are proposed.