Ofloxacin degradation in chloride-containing medium by photo-assisted sonoelectrochemical process using a mixed metal oxide anode

Author(s)

Antonelli, Raissa ; Malpass, Geoffroy Roger Pointer ; da Silva, Meuris Gurgel Carlos ; Vieira, Melissa Gurgel Adeodata

• Document type: Journal article
• Source: JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING; v. 10, n. 2, p. 12-pg., 2022-04-01.

Abstract

A photo-assisted sonoelectrochemical (UV/US/EC) hybrid process using a mixed metal oxide (MMO) (e.g., Ti/ Ru0.3Ti0.7O2) electrode was evaluated with the aim of investigating the degradation and mineralization of ofloxacin (OFL) in a chloride-containing medium. Under optimized condition (30 mA/cm(2), 0.05 mol/L NaCl, 10 mL/min, and natural pH), the OFL concentration decayed to 0 in 5 min and, after only 60 min of treatment, similar to 60% TOC was removed. The comparison of different combinations of UV, US, and EC techniques showed that the UV/US/EC and UV/EC techniques were the most advantageous, due to the production of highly reactive radicals through photolysis of electrochemically generated active chlorine species. A significant reduction in OFL was only achieved in the presence of NaCl, compared to Na2SO4 as supporting electrolyte, demonstrating that DSA (R) electrodes have high electrocatalytic activity for chlorine evolution. Under real conditions, the percentage of OFL removal from the river water sample was 97% after 10 min of treatment. Phytotoxicity tests indicated that it is possible to reduce the toxicity of the solution using NaCl as supporting electrolyte. In addition, a mineralization pathway for OFL was proposed for the process in question. (AU)

• FAPESP's process: 16/05007-1 - Removal of residual drug in aqueous solution by alternative adsorbents
• Grantee: Meuris Gurgel Carlos da Silva
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/11353-8 - Brazilian Water Research Center (BWRC)
• Grantee: Lauro Tatsuo Kubota
• Support Opportunities: Research Grants - Research Centers in Engineering Program