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A performance de nanopartículas de ferrite de cobalto, ferrite de cobalto recoberta por carbono preparada por uma metodologia tradicional e ferrite de cobalto preparada por metodologia verde foi avaliada na remoção de paracetamol (PCM), escolhido como poluente modelo, por um processo de oxidação húmida com peróxido de hidrogénio (CWPO). O núcelo magnético foi sintetizado por sol-gel, e na metodologia tradicional de recobrimento de carbono foi considerado resorcinol/formaldeído como precursores de carbono, enquanto que na metodologia verde foi considerado phloroglucinol/ácido glioxílico. Todas as nanopartículas magnéticas (NPMs) apresentaram atividade na remoção de PCM por CWPO. Ambas as NPMs recobertas com carbono apresentaram resultados melhores que o núcleo não recoberto, devido à presença da camada de carbono à volta do núcleo, que também tem atividade pelas propriedades eletrónicas do recobrimento de carbono. O catalisador recoberto pela metodologia verde possui uma decomposição de peróxido de hidrogénio mais controlada. O teste de reutilização do catalisador mostrou a estabilidade do material, com perfis de concentração similares e uma remoção de PCM mais rápida que na primeira utilização The performance of non-coated magnetic nanoparticle (MNPs) based on cobalt ferrite (CoFe2O4), and of carbon-coated cobalt ferrite prepared by a traditional method (CoFe2O4@C1), and by a greener method (CoFe2O4@C2) was assessed in the removal of paracetamol (PCM), used as model pharmaceutical pollutant, by catalytic wet peroxide oxidation (CWPO). The magnetic core was synthesized by sol-gel methodology, and the traditional method for carbon coating considered resorcinol and formaldehyde as carbon precursors. In contrast, the greener method was performed considering phloroglucinol and glyoxylic acid as carbon precursors. All MNPs presented activity on the removal of PCM by CWPO. Both carbon-coated MNPs overcome the results obtained with the bare core, due to the carbon layer covering the core, which can also have catalytic activity. The catalyst coated by the greener method (CoFe2O4@C2) shows a more controlled decomposition of hydrogen peroxide. A reutilization test performed to evaluate the stability of this catalyst showed complete removal of PCM faster than in the first usage, with a similar concentration trend profile in both repetitions. Adriano S. Silva thanks his doctoral Grant with reference SFRH/BD/151346/2021 financed by the Portuguese Foundation for Science and Technology (FCT), with funds from NORTE2020, under MIT Portugal Program. Fernanda F. Roman acknowledges the national funding by FCT through the individual research grant SFRH/BD/143224/2019. This work was financially supported by UIDB/00690/2020 (CIMO), LA/P/0045/2020 (ALiCE), UIDB/50020/2020 (LSRE-LCM), and the project RTChip4Theranostics, with the reference NORTE- 01-0145-FEDER-029394. Jose L. Diaz De Tuesta acknowledges the financial support through the program of “Atracción al Talento” of “Comunidad de Madrid” (Spain) for the individual research grant 2020-T2/AMB-19836. info:eu-repo/semantics/publishedVersion |
