New electrochemical reactor design for emergent pollutants removal by electrochemical oxidation

Author(s)

Montenegro-Ayo, Renato ; Perez, Tzayam ; Lanza, Marcos R. V. ; Brillas, Enric ; Garcia-Segura, Sergi ; dos Santos, Alexsandro J.

• Document type: Journal article
• Source: Electrochimica Acta; v. 458, p. 11-pg., 2023-05-12.

Abstract

This paper presents the theoretical and experimental confirmation of the performance of a novel pre-pilot reactor design implementing a boron-doped diamond (BDD) anode to destroy emerging pollutants by electrochemical oxidation. Turbulent flow simulation and secondary current distribution modeling with a COMSOL Multiphysics software were used to assess the engineering capabilities of the reactor along with the oxidant BDD((OH)-O-center dot) electrogeneration at the anode. The antibiotic ciprofloxacin (CIP) was chosen as model molecule to assess the oxidation power achieved with the pre-pilot batch plant. In sulfate medium where BDD((OH)-O-center dot) was the main oxidant, faster degradation was determined by increasing current density, CIP content, and pH. The effect of pH was explained by the transformation of the cationic form of CIP in acidic medium into its more easily oxidizable anionic form in alkaline medium. In chloride medium, CIP was more rapidly removed by the faster attack of the generated active chlorine. The degradation was decelerated in carbonate medium by its scavenging effect and in the presence of humic acid by its competitive oxidation with BDD((OH)-O-center dot). The antibiotic abatement also dropped down in tap water and synthetic urine. An almost total mineralization was achieved with a constant energy cost per unit COD mass of 0.6 +/- 0.1 kWh (g COD)(-1). The initial N of CIP was pre-eminently converted into nitrate, alongside nitrite and ammonia to lesser extent. Recalcitrant acetic, oxalic, and formic acids were detected as final carboxylic acids. (AU)

• FAPESP's process: 17/10118-0 - Study and application of electrochemical technology for the analysis and degradation of endocrine interferents: materials, sensors, processes and scientific dissemination
• Grantee: Marcos Roberto de Vasconcelos Lanza
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 14/50945-4 - INCT 2014: National Institute for Alternative Technologies of Detection, Toxicological Evaluation and Removal of Micropollutants and Radioactivies
• Grantee: Maria Valnice Boldrin
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 21/08701-4 - Application of electrochemically driven technologies to remove real concentrations of persistent organic pollutants in complex water matrices
• Grantee: Alexsandro Jhones dos Santos
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 19/20634-0 - Treatment of wastewater contaminated with endocrine interferences through the application of electrochemical advanced oxidation processes: synergistic effect of different carbon supported cathodes
• Grantee: Alexsandro Jhones dos Santos
• Support Opportunities: Scholarships in Brazil - Post-Doctoral