Towards Use of Persulfate Electrogenerated at Boron Doped Diamond Electrodes as Ex-Situ Oxidation Approach: Storage and Service-Life Solution Parameters
Autor: | Karla C. F. Araújo, Karyn N. O. Silva, Mayra K. S. Monteiro, Djalma R. da Silva, Marco A. Quiroz, Elisama V. dos Santos, Carlos A. Martínez-Huitle |
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Rok vydání: | 2022 |
Předmět: | |
Zdroj: | Journal of The Electrochemical Society. 169:033506 |
ISSN: | 1945-7111 0013-4651 |
DOI: | 10.1149/1945-7111/ac59f8 |
Popis: | To date, a wide range of synthetic and real effluents have been treated using in situ electrochemically driven BDD-SO4 2−/SO4 ·−/S2O8 2− systems to eliminate persistent organic pollutants and microorganisms. Although reactive sulfate-based species are electrochemically generated in situ with free heterogenous ·OH radicals, SO4 2−/SO4 ·−/S2O8 2− species have a half-life greater than that of the ·OH radicals. However, no information has been published regarding the properties of the oxidant solution after its electrochemical synthesis. Here, an electrochemical BDD-SO4 2−/SO4 ·−/S2O8 2− 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 °C) or cold-persulfate (10 °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. |
Databáze: | OpenAIRE |
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