Towards Use of Persulfate Electrogenerated at Boron Doped Diamond Electrodes as Ex-Situ Oxidation Approach: Storage and Service-Life Solution Parameters

Autor(es)

Araujo, Karla C. F. ; Silva, Karyn N. O. ; Monteiro, Mayra K. S. ; da Silva, Djalma R. ; Quiroz, Marco A. ; dos Santos, Elisama, V ; Martinez-Huitle, Carlos A.

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Electrochemical Society; v. 169, n. 3, p. 9-pg., 2022-03-01.

Resumo

To date, a wide range of synthetic and real effluents have been treated using in situ electrochemically driven BDD-SO42-/SO4 center dot-/S2O82- systems to eliminate persistent organic pollutants and microorganisms. Although reactive sulfate-based species are electrochemically generated in situ with free heterogenous (OH)-O-center dot radicals, SO42-/SO4 center dot-/S2O82- species have a half-life greater than that of the (OH)-O-center dot radicals. However, no information has been published regarding the properties of the oxidant solution after its electrochemical synthesis. Here, an electrochemical BDD-SO42-/SO4 center dot-/S2O82- system was evaluated in terms of solution oxidation power as a function of storage temperature, storage time, and ex situ applicability. Results clearly show that storage temperature has an influence on the storage and service-life of the solutions called fresh-persulfate (25 degrees C) or cold-persulfate (10 degrees C). Greater stability in the cold-persulfate solution was observed, as a function of time, and it was effective in degrading organic pollutants as an ex situ oxidation approach, eliminating 80.73%, 79.25%, and 63.25% after 120 min for methyl orange dye, 1,4-benzoquinone (1,4-BQ), and caffeine, respectively. Cold-persulfate solution also proved to be a feasible off-grid technology after 14 days storage. These results contribute to understanding of the fundamentals of sulfate aqueous solutions as precursors of sulfate-based oxidizing solutions and their applications. (C) 2022 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited. (AU)

• Processo FAPESP: 19/13113-4 - Processos foto (eletro) catalíticos e fotoeletro-fenton para eliminar contaminantes emergentes de águas de rejeito industriais
• Beneficiário: Maria Valnice Boldrin
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• 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