Sulfate pollution: evidence for electrochemical production of persulfate by oxidizing sulfate released by the surfactant sodium dodecyl sulfate

There is increasing concern about contamination by surfactants that are used to extract organic pollutants during remediation of polluted soils and aquifers. For instance, the surfactant sodium dodecyl sulfate may produce sulfate, which is a pollutant at high concentrations. Reports suggest that whe...

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Detalles Bibliográficos
Autores: Santos, Elisama Vieira dos, Araújo, Karla C. de F., Barreto, Jéssica P. de P., Cardozo, Jussara C., Araújo, Danyelle M. de, Martínez‐Huitle, Carlos Alberto
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2018
País:Brasil
Institución:Universidade Federal do Rio Grande do Norte (UFRN)
Repositorio:Repositório Institucional da UFRN
Idioma:inglés
OAI Identifier:oai:repositorio.ufrn.br:123456789/29772
Acceso en línea:https://repositorio.ufrn.br/jspui/handle/123456789/29772
Access Level:acceso abierto
Palabra clave:Diamond electrode
Persulfate
Sodium dodecyl sulfate
Sulfate release
Surfactant
Descripción
Sumario:There is increasing concern about contamination by surfactants that are used to extract organic pollutants during remediation of polluted soils and aquifers. For instance, the surfactant sodium dodecyl sulfate may produce sulfate, which is a pollutant at high concentrations. Reports suggest that when remediation involves sodium dodecyl sulfate and electrochemical treat-ments, SO42− ions could be produced then oxidized to persulfate (S2O82−). However, there is few knowledge on the mechanism of electrochemical production of sulfate and persulfate. Here, we tested for frst time the electrochemical production of persulfate from sulfate released by oxidation of sodium dodecyl sulfate, using anodic oxidation with boron-doped diamond. Results show a high efciency of persulfate production, reaching 2.5 μM, when 500 mg/L of surfactant in 0.05 mol/L of Na2SO4 was electrolyzed at 60 mA cm−2, by comparison with only 0.7 μM of persulfate without surfactant in solution. Thisefciency is explained by electrogeneration of hydroxyl radicals and persulfate. Results also show that 97% of the surfactant is transformed by fragmentation and oxidation, as revealed by particle size measurements