| Texto completo | |
| Autor(es): |
Silva, Taynara O.
;
Santos, Gessica O. S.
;
Lanza, Marcos Roberto V.
;
Ruotolo, Luis Augusto M.
Número total de Autores: 4
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Chemical Engineering Science; v. 319, p. 12-pg., 2026-07-31. |
| Resumo | |
A comparative evaluation was conducted on carbon-based materials, polyaniline-derived activated carbon (PAC) and Printex L6 carbon (PL6C), aiming to understand their activity and selectivity towards the two-electron oxygen reduction reaction (2e- ORR) to obtain H2O2 for application in an advanced oxidation process (AOPs). The electrochemical behavior of each carbon cathode was evaluated using the rotating ring-disk electrode (RRDE) technique. The RRDE analyses showed that PAC exhibited lower overpotential for the 2e- ORR, indicating higher activity, whereas PLC6 showed higher selectivity towards H2O2 (70 %, compared to 55 % for PAC). The performance of these materials was investigated using the gas diffusion electrode (GDE) approach for H2O2 electrogeneration. Under optimal conditions, H2O2 electrogeneration using the PAC-GDE presented superior Faradaic efficiency and lower energy consumption, compared to the PL6C-GDE, which indicated the benefit of low overpotential. However, the PL6C-GDE produced a higher H2O2 concentration after 90 min due to its greater selectivity. Finally, ciprofloxacin (CIP) was used as a model contaminant for degradation studies using different AOPs, including electrochemical oxidation (EO), UVC photolysis, and hybrid H2O2-based systems (EO/ H2O2/UVC and EO/H2O2). For the H2O2-based process, operating conditions were optimized to reach 200 mg L- 1 H2O2, a concentration commonly reported as sufficient for the degradation of organic micropollutants. Among AOPs tested, EO/H2O2/UVC was found to be most efficient, with the PL6C-GDE as the most favorable electrode (85.5 % removal). Therefore, the kinetics of H2O2 generation directly affect the degradation rates of organic compounds, indicating that this parameter is more important than low overpotential for electrochemically-driven H2O2-based treatments. (AU) | |
| Processo FAPESP: | 20/02743-4 - Filmes de Fe/RuO2-TiO2 suportados em feltro de carbono para degradação do norfloxacino por processo eletro-fenton heterogêneo |
| Beneficiário: | Géssica de Oliveira Santiago Santos |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 23/08720-4 - Desenvolvimento de novos eletrodos de difusão gasosa constituídos por carbono de precursores biomássicos e sua aplicação para desinfecção por peróxido de hidrogênio eletrogerado |
| Beneficiário: | Taynara Oliveira Silva |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 22/12895-1 - Processos avançados para a degradação de poluentes emergentes: materiais catalíticos, sensores eletroanalíticos e divulgação científica |
| Beneficiário: | Marcos Roberto de Vasconcelos Lanza |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |