Use of WO2.72 Nanoparticles/Vulcan® XC72 GDE Electrocatalyst Combined with the Photoelectro-Fenton Process for the Degradation of 17α-Ethinylestradiol (EE2)

• Published in: Electrocatalysis 2022-07, Vol.13 (4), p.457-468
• Main Authors: Machado, Maria Lucia O., Paz, Edson C., Pinheiro, Victor S., de Souza, Rafael Augusto S., Neto, Ana Maria Pereira, Gaubeur, Ivanise, dos Santos, Mauro C.
• Format: Article
• Language: English
• Subjects: Anodes; Catalysis; Cathodes; Chemistry; Chemistry and Materials Science; Degradation; Deionization; Diamonds; Drinking water; Electrocatalysts; Electrochemistry; Energy Systems; Gaseous diffusion; High performance liquid chromatography; Hormones; Hydrogen peroxide; Nanoparticles; Organic carbon; Organic matter; Original Research; Oxalic acid; Oxidation; Physical Chemistry; Potassium sulfate; Water reuse
• ISSN: 1868-2529; 1868-5994
• DOI: 10.1007/s12678-022-00724-8

This study proposed the use of electrochemical advanced oxidation processes (EAOPs) for the degradation of 17α-ethinylestradiol (EE2). Initially, hydrogen peroxide electrogeneration was performed using a gas diffusion electrode (GDE) cathode prepared with the electrocatalyst Vulcan® XC72 modified with WO 2.72 nanoparticles and a boron-doped diamond (BDD) anode. Subsequently, the photoelectrodegradation of 20 mg L −1 EE2 was performed in a synthetic solution under the following conditions: 0.50 mmol L −1 Fe 2+ , 0.10 mol L −1 K 2 SO 4 , pH 3.0, 20 °C at different current densities ( j  = 150, 200, 250, or 300 mA cm −2 ). Degradation efficiency was evaluated by determining the organic matter content through total organic carbon (TOC) analyses. Finally, TOC reductions of 74.5, 88.4, 88.3, and 93.6% were obtained for synthetic EE2 solutions prepared in deionized water, reuse water, tap water, and mineral water, respectively, when performing degradation at 300 mA cm −2 . Intermediate compounds were identified using high-performance liquid chromatography (HPLC), and the predominance of oxalic acid was observed. The use of photoelectro-Fenton process joined with a cathode composed of an electrocatalyst of Vulcan® XC72 modified with WO 2.72 nanoparticles and a BDD anode were very efficient to degrade synthetic EE2 solutions in different water matrices, probing that Vulcan® XC72 modified with WO 2.72 nanoparticles is not only an excellent material for dyes degradation but also to hormones remotion. Graphical abstract