Niobium on BEA dealuminated zeolite for high selectivity dehydration reactions of ethanol and xylose into diethyl ether and furfural

Registro completo de metadados
MetadadosDescriçãoIdioma
Autor(es): dc.creatorValadares, Deborah da Silva-
Autor(es): dc.creatorClemente, Maria Clara Hortêncio-
Autor(es): dc.creatorFreitas, Elon Ferreira de-
Autor(es): dc.creatorMartins, Gesley Alex Veloso-
Autor(es): dc.creatorDias, José Alves-
Autor(es): dc.creatorDias, Silvia Clara Loureiro-
Data de aceite: dc.date.accessioned2021-10-14T17:29:50Z-
Data de disponibilização: dc.date.available2021-10-14T17:29:50Z-
Data de envio: dc.date.issued2020-07-24-
Data de envio: dc.date.issued2020-07-24-
Data de envio: dc.date.issued2019-
Fonte completa do material: dc.identifierhttps://repositorio.unb.br/handle/10482/39298-
Fonte completa do material: dc.identifierhttps://doi.org/10.3390/nano10071269-
Fonte completa do material: dc.identifierhttps://orcid.org/0000-0003-4622-2445-
Fonte completa do material: dc.identifierhttps://orcid.org/0000-0003-0042-0091-
Fonte completa do material: dc.identifierhttps://orcid.org/0000-0002-3351-9226-
Fonte: dc.identifier.urihttp://educapes.capes.gov.br/handle/capes/609318-
Descrição: dc.description: In this work, we investigated the role of solid-state dealumination by (NH4)2SiF6 (25% Al removal and 13% Si insertion), the impregnation of niobium (10, 18, and 25 wt. %) on dealuminated *BEA (DB) zeolite and their catalytic properties in ethanol and xylose transformations. Among all the studied catalysts, 18%Nb-DB showed increased mesoporosity and external areas. A leveling effect in the number and strength of the proposed two sites (Brønsted and Lewis) present in the catalyst (n1 = 0.24 mmol g−1 , −∆H1 = 49 kJ mol−1 , and n2 = 0.20 mmol g−1 , –∆H2 = 42 kJ mol−1 ) in the catalyst 18%Nb-DB, might be responsible for its good activity. This catalyst presented the highest selectivity for diethyl ether, DEE (97%) with 61% conversion after 50 ethanol pulses at 230 ◦C (turnover number, TON DEE = 1.15). These features allowed catalytically fruitful bonding of the ethanol molecules to the neighboring sites on the channels, facilitating bimolecular ether formation through a possible SN2 mechanism. The same catalyst was active and selective for transformation of xylose at 180 ◦C, showing 64% conversion and 51% selectivity for furfural (TON Furfural = 24.7) using water as a green solvent.-
Formato: dc.formatapplication/pdf-
Publicador: dc.publisherMDPI-
Direitos: dc.rightsAcesso Aberto-
Direitos: dc.rights© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).-
Palavras-chave: dc.subjectZeólitas-
Palavras-chave: dc.subjectNióbio-
Palavras-chave: dc.subjectDesidratação de etanol-
Palavras-chave: dc.subjectÉter Dietílico-
Palavras-chave: dc.subjectXilose-
Palavras-chave: dc.subjectFurfural-
Título: dc.titleNiobium on BEA dealuminated zeolite for high selectivity dehydration reactions of ethanol and xylose into diethyl ether and furfural-
Tipo de arquivo: dc.typelivro digital-
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