Cr-Containing Rare-Earth Substituted Yttrium Iron Garnet Ferrites: Catalytic Properties in the Ethylbenzene Oxidation
Por:
do Carmo, Jose Vitor C., Bezerra, Rita de Cassia F., Guerra, Y., Pena-Garcia, R., Oliveira, Alcineia C., Padron-Hernandez, E., Saraiva, Gilberto D., Soares, Joao M., Castro, Antonio Joel R., Tehuacanaero-Cuapa, Samuel, Rodriguez-Aguado, Elena, Rodriguez-Castellon, Enrique
Publicada:
1 sep 2022
Resumen:
A series of the Cr-containing erbium substituted yttrium iron garnet
ferrites (ECYIG) was synthesized with distinct Cr amounts, herein
referred to as Y-3(Er0.02Fe5Cr1-x)O-12, where x refers to Cr amounts
from 0 to 0.05. The catalytic performance of the solids was investigated
in ethylbenzene oxidation in the presence of hydrogen peroxide to assess
the role of Cr and Er present in the YIG garnet lattice for fine
chemistry compound production. Raman spectroscopy, HRTEM, EPR and FTIR
revealed that the insertion of Er (at a fixed amount of 2%) in
dodecahedral sites had a great impact on the catalytic activity of the
garnets. Both Er3+ and Y3+ in the lattice simultaneously provided
structural stability to the garnet structure in any harsh environment.
XPS and EPR indicated that the Cr3+ ions replaced those of Fe3+ located
in both octahedral and tetrahedral sites of the YIG garnets. The Cr3+
ions acted as electronic promoter to increase the oxidation rate of the
Fe3+ active species responsible for activating the EB molecule. SEM-EDS
demonstrated that the solids having Cr amounts lower than 4%
experienced the most severe deactivation due to the Cr leaching and
strong carbon species adsorption on the surface of the catalysts, which
decreased their efficiency in the reaction.
Filiaciones:
Univ Fed Ceara, Dept Quim Analit & Fis Quim, Campus Pici,Bloco 940, BR-60455760 Fortaleza, Ceara, Brazil
Univ Fed Piaui, Dept Fis, Campus Univ Ministro Petronio Portella, BR-64049550 Teresina, Brazil
Univ Fed Rural Pernambuco, Unidade Academ Cabo Santo Agostinho, BR-54589899 Cabo De Santo Agostinho, Brazil
Univ Fed Pernambuco, Dept Fis, Ave Prof Luiz Freire,Cidade Univ, BR-50740540 Recife, PE, Brazil
Univ Estadual Ceara, Fac Educ Ciencias & Letras Sertao Cent, BR-63902098 Quixada, Brazil
Univ Estado Rio Grande do Norte UERN, Dept Fis, BR 110 Km 48,R Prof Antonio Campos Costa & Silva, BR-59625620 Mossoro, Brazil
Univ Fed Ceara, Campus Quixada, BR-63902580 Quixada, Brazil
Univ Autonoma Mexico, Inst Fis, Dept Fis, Circuito Invest S-N,Ciudad Univ, Coyoacan 4510, Mexico
Univ Malaga, Fac Ciencias, Dept Quim Inorgan, Malaga 29071, Spain
gold, Green Published, All Open Access, Gold, Green
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