Photoelectrocatalytic treatment of levofloxacin using Ti/MMO/ ZnO electrode

Autor(es)

Goulart, Lorena A. ^{[1, 2]} ; Moratalla, Angela ^[2] ; Lanza, Marcos R. V. ^[1] ; Saez, Cristina ^[2] ; Rodrigo, Manuel A. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Chem Sao Carlos, POB 780, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Castilla La Mancha, Dept Chem Engn, Campus Univ S-N, Ciudad Real 13071 - Spain

• Tipo de documento: Artigo Científico
• Fonte: Chemosphere; v. 284, DEC 2021.
• Citações Web of Science: 0

Resumo

Here, the antibiotic levofloxacin (LFX) widely used and detected in the environment was degraded by photoelectrolysis using a new electrode based on zinc oxide (ZnO) and a mixture of mixed oxides of ruthenium and titanium (MMO). The influence of the potential and irradiation of UV light was investigated in the photostability of the Ti/MMO/ZnO electrode and in the degradation of the antibiotic. The experiments were conducted at different pH values (5.0, 7.0 and 9.0) in sodium sulfate solution in a glass reactor with central lighting. It was observed that the new Ti/MMO/ZnO electrode has good stability under light irradiation and potential, presenting excellent photocurrent and high photoactivity in LFX photoelectrolysis. The removal efficiency of the compound was directly related to the formation of oxidizing species in solution, the photo-generated charges on the electrode and the electrostatic characteristics of the molecule. The mineralization rate, the formation of reaction intermediates and short chain carboxylic acids (acetic, maleic, oxalic and oxamic acid), in addition to the formation of N-mineral species (NO3- and NH4+) was dependent on the pH of the solution and the investigated processes: photoelectrolysis was more efficient than photolysis, which, in turn, was more efficient than electrolysis. The synergistic effect and the high rate of degradation of LFX after 4.0 h of treatment (100%) observed in photoelectrolysis at alkaline pH, was associated with the high stability of the Ti/MMO/ZnO electrode at this pH, the photoactivation of sulfate ions and the ease generation of oxidizing radicals, such as center dot OH. (AU)

• Processo FAPESP: 19/04084-0 - Eletrodos de heterojunção de óxidos aplicados na fotoeletrocatálise de antibióticos em reatores de fluxo
• Beneficiário: Lorena Athie Goulart
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado
• Processo FAPESP: 14/50945-4 - INCT 2014: Instituto Nacional de Tecnologias Alternativas para Detecção, Avaliação Toxicológica e Remoção de Micropoluentes e Radioativos
• Beneficiário: Maria Valnice Boldrin
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 17/10118-0 - Estudo e aplicação da tecnologia eletroquímica para a análise e a degradação de interferentes endócrinos: materiais, sensores, processos e divulgação científica
• Beneficiário: Marcos Roberto de Vasconcelos Lanza
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 16/08760-2 - Heterojunções de NiO/ZnO e CuO/ZnO aplicadas na degradação fotoeletrocatalítica de trimetoprim e levofloxacina
• Beneficiário: Lorena Athie Goulart
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado