Banca de DEFESA: ADRIANA PERPETUA FIGUEIREDO PAULISTA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ADRIANA PERPETUA FIGUEIREDO PAULISTA
DATE: 28/02/2020
TIME: 14:00
LOCAL: Auditório do CCET
TITLE:

Synthesis of the Fe-Co alloy from hybrid spheres using carboxymethylcellulose as template and its application in catalysis

KEY WORDS:

FeCo alloy, Hybrid spheres, Carboxymethylcellulose, Magnetic catalyst.

PAGES: 60
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Físico-Química
SPECIALTY: Cinética Química e Catálise
SUMMARY:

Hybrid spheres is confirmed to be an efficient method in the synthesis of Fe-Co alloy. The carboxymethylcellulose-based organic precursor (CMC) was added dropwise to a solution containing Fe³⁺ and Co²⁺ , leading to the formation of the hybrid spheres from the complexation of the metal cations with the radicals present in the biopolymer (cross-linking process). The hybrid spheres were calcined in air atmosphere leading to the formation of Fe and Co based oxide. After, it was reduced with H₂ flow to form the FeCo alloy. The alloy was applied in the ethylbenzene dehydrogenation reaction to styrene production (high added value product). In order to characterize the obtained materials, it was used the infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TG), magnetometry and gas chromatography (GC). FTIR confirms the complexation mechanism between metal ions and CMC and the complete oxidation of the biopolymer after calcination. The diffractograms confirm the formation of the FeCo alloy after reduction under H₂ atmosphere. TG indicates the minimum temperature at which the alloy is oxidized, confirming the chemical resistance of the FeCo alloy against the oxidizing atmosphere. The magnetic hysteresis curves confirm the ferromagnetic nature of the FeCo alloy. The ethylbenzene dehydrogenation reaction was selective for the formation of styrene in the presence of the FeCo alloy, confirming the interesting properties of the iron-based catalysts for dehydrogenation reactions.

BANKING MEMBERS:
Externo ao Programa - 1804952 - FERNANDO JOSÉ VOLPI EUSÉBIO DE OLIVEIRA
Externo à Instituição - JOÃO MARIA SOARES - UERN
Externo à Instituição - RÔMULO BATISTA VIEIRA - UNEB
Presidente - 2087667 - TIAGO PINHEIRO BRAGA