Banca de DEFESA: JOHNATAN DE OLIVEIRA SOARES

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : JOHNATAN DE OLIVEIRA SOARES
DATE: 19/05/2022
TIME: 14:00
LOCAL: Auditório do Química III
TITLE:

SYNTHESIS, CHARACTERIZATION AND PHOTOCATALYTIC ACTIVITY OF OXIDES BASED ON CoFe2O4/Fe2O3 dispersed in KIT-6

KEY WORDS:

CoFe₂O₄, Fe₂O₃, Ferrite, KIT-6, Photocatalysis.

PAGES: 112
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Físico-Química
SPECIALTY: Cinética Química e Catálise
SUMMARY:

Some poisonous compounds are resistant to degradation by common effluent treatments. For this reason, development of new methods and materials capable of solving this problem. Thus, the present work aimed to synthesize and characterize the solid CoFe₂O₄/Fe₂O₃-KIT-6, and to evaluate its performance in the photocatalytic degradation of Phenol and ultra RGB red remazol dye.The material obtained was characterized by X-ray Diffraction (XRD), Mössbauer Spectroscopy, X-ray Fluorescence (FRX), Infrared with adsorption of pyridine and NO (FTIR), Raman spectroscopy, Thermogravimetric analysis (TGA), adsorption/desorption of N₂, Temperature Programmed Reduction (TPR-H₂), Temperature Programmed Desorption (TPD-CO₂), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Diffuse Reflectance Spectroscopy (DRS). From the XRD, N₂, Raman, TG and Mössbauer fission analyses, it was possible to identify that the desired CoFe₂O₄/Fe₂O₃ phase was obtained supported on KIT-6, which maintained its structural properties. The bands at 1450, 1490 and 1609 cm^-1 in the FTIR-pyridine and the FTIR-NO profile indicate the presence of Lewis acidic sites, while the TPD-CO₂ profile showed a large amount of weak basic sites. The TPR-H₂ result shows a reduction profile with significant events around 450°C and 850°C referring to the reduction of Fe and Co. The SEM and TEM images confirm that the morphology of the support was not significantly altered after metal impregnation. The band-gap energy of 1.7 eV indicates that the compound can be applied in photocatalytic degradation under UV/visible light, with the possibility of magnetic separation at the end of the reaction. The photocatalysis results indicate low degradation of phenol under the applied conditions and complete degradation of the remazol red ultra RGB dye in 1 hour of reaction. The combination of the proposed photocatalyst with the anatase phase (TiO₂) shows significant improvements in the degradation process even in the absence of H₂O₂.

BANKING MEMBERS:
Externa à Instituição - ANA PAULA DE MELO ALVES - UFPB
Interna - 2413537 - POLLYANA SOUZA CASTRO
Presidente - 2087667 - TIAGO PINHEIRO BRAGA