Banca de DEFESA: JOÃO OCTÁVIO MEDEIROS PIRES

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : JOÃO OCTÁVIO MEDEIROS PIRES
DATA : 17/04/2018
HORA: 14:30
LOCAL: AUDITÓRIO DO NUPEG
TÍTULO:

Synthesis, characterization and evaluation of photocatalytic potential under visible light of Ce2(MoO4)3/TiO2 composite.

 

PALAVRAS-CHAVES:

Cerium molybdate, titanium dioxide, heterogeneous catalysis, EDTA Citrato method, wet doping.

PÁGINAS: 88
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Química
RESUMO:

Ce2(MoO4)3/TiO2 composites (cerium molybdate and titanium dioxide) with different compositions were prepared by combined complexation method EDTA/Citrate and by the wet doping method. The obtained materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and diffuse reflectance spectroscopy (DRS). The material catalytic potential was evaluated by spectrophotometry, in which the dye concentration variation (Maxilon Blue and Erionyl Yellow at 10ppm) was evaluated in a reactor with 30, 60, 90 and 120 minute batch reaction at 45ºC, pH = 6, with visible light incidence and 200mg / L of catalyst. According to the results of the XRD, it was verified that the obtained compounds presented the expected phases. Through the images of the SEM it was possible to observe that there was a change in sizes and formats of the base material (TiO2) due to the incorporation of the cerium molybdate. It was also verified through SEM that the material was not homogeneous for the wet doping method done with 10%. The EDS results confirmed the presence of elements that were used to form the final compound and presented a deviation of 2.3-5.7% between the theoretical and the experimental composition, justified by the synthesis and doping method. By the ERD analysis, it was certified that there was no significant change in the bandgap of the base material (TiO2) when introducing Ce2(MoO4)3. Commercial TiO2 was used as comparison basis for the photocatalysis tests. The photocatalytic potential was evaluated according to base points, considering photolysis, adsorption and photocatalysis, thus requiring tests with and without light. For the yellow acid dye (Yellow Erionyl) the photolysis was not significant, the material obtained values of up to 25% of adsorption and obtained as best photocatalyst the 5 wt% Ce2(MoO4)3/TiO2 obtained by impregnation, which caused 42% remotion. For the basic blue dye (Maxilon Blue) there was photolysis of up to 27% in 120 minutes, it obtained the best results of adsorption and degradation when used with the base material, reaching 67.7% and 94.67% respectively at the end of 120 minutes.

MEMBROS DA BANCA:
Presidente - 349801 - CARLSON PEREIRA DE SOUZA
Interno - 2929066 - ANDRE LUIS LOPES MORIYAMA
Externo ao Programa - 338292 - JOAO BOSCO LUCENA DE OLIVEIRA
Externo à Instituição - GILSON GARCIA DA SILVA - IFRN