Boron doped diamond electrooxidation of 6:2 fluorotelomers and perfluorocarboxylic acids. Application to industrial wastewaters treatment
The aim of this study was to determine the viability of electrochemical oxidation to degrade and mineralize poly- and perfluoroalkyl substances (PFASs) in wastewaters from an industrial facility dedicated to the production of side-chain-fluorinated polymers and fluorotelomer-based products for fire-...
| Autores: | , , , , , , |
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| Formato: | artículo |
| Fecha de publicación: | 2017 |
| País: | España |
| Recursos: | Universidad de Cantabria (UC) |
| Repositorio: | UCrea Repositorio Abierto de la Universidad de Cantabria |
| Idioma: | inglés |
| OAI Identifier: | oai:repositorio.unican.es:10902/11108 |
| Acesso em linha: | http://hdl.handle.net/10902/11108 |
| Access Level: | acceso abierto |
| Palavra-chave: | Poly- and perfluoroalkyl substances (PFASs) 6:2 FTSA and 6:2 FTAB Perfluorocarboxylic acids Electrochemical oxidation Boron doped diamond anode Industrial wastewater |
| Resumo: | The aim of this study was to determine the viability of electrochemical oxidation to degrade and mineralize poly- and perfluoroalkyl substances (PFASs) in wastewaters from an industrial facility dedicated to the production of side-chain-fluorinated polymers and fluorotelomer-based products for fire-fighting foams. 6:2 fluorotelomer sulfonamide alkylbetaine (6:2 FTAB, 1111 μg/L), 6:2 fluorotelomer sulfonic acid (6:2 FTSA, 242.5 μg/L) and 6:2 fluorotelomer sulfonamide propyl N,N dimethylamine (M4, 34.4 μg/L) were the most abundant PFASs in the industrial wastewater, that also contained perfluorocarboxylic acids (ΣPFCAs, 12.2 μg/L), high TOC and chloride as main anion. 2 L samples were treated in bench scale experiments performed at a current density of 50 mA/cm2, in a commercial cell equipped with a boron doped diamond (BDD) anode (70 cm2). 97.1% of the initial PFASs content was removed after 8 h of electrochemical treatment. Furthermore, the TOC removal (82.5%) and the fluoride release confirmed the PFASs mineralization. Based on the evolution of the different PFASs, electrochemical degradation pathways were proposed. Fluorotelomers sulfonamides 6:2 FTAB and M4 would be degraded into 6:2 FTSA, which conversely would give rise to PFHpA and preferentially PFHxA. The latter PFCAs were transformed into shorter-chain PFCAs, and eventually into CO2 and fluoride. The reported results support the technical viability of BDD electrooxidation for the treatment of PFASs in industrial wastewater. |
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