Banca de DEFESA: MIKAELY LIZANDRA MOREIRA DE ASSIS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : MIKAELY LIZANDRA MOREIRA DE ASSIS
DATE: 28/01/2021
TIME: 09:00
LOCAL: Remotamente pelo google meet
TITLE:

SYNTHESIS, CHARACTERIZATION AND APPLICATION OF THE PALYGORSKITE/TITANIUM DIOXIDE NANOCOMPOSITE IN PHOTOCATALYTIC DEGRADATION OF TEXTILE DYES

KEY WORDS:

 textile dyes. Novacron blue. Novacron yellow. photocatalysis. titanium dioxide. palygorskite.

PAGES: 80
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Analítica
SPECIALTY: Análise de Traços e Química Ambiental
SUMMARY:

One of the biggest environmental problems is due to industrial activity, in which the contamination of water resources with post-production waste occurs, causing adverse effects to the ecosystem. The effluents of industrial dyes present a great risk to the health of biodiversity, in most cases, they are toxic, persistent organic compounds that are difficult to remove by conventional treatments, in addition to presenting themselves as carcinogenic materials. The development or improvement of techniques for effluent treatment are of great interest, since the objective is to search for low-cost synthesis routes that generate less toxic waste or by-products. The photocatalytic discoloration of industrial dyes, Novacron blue (AZN) and Novacron yellow (AMN), were investigated using TiO₂-based composites supported on natural palygorskite (TiP10 and TiP30). The method consisted of synthesizing the composites starting from a physical mixture of TiO₂ and natural palygorskite in the presence of alcohol, for impregnation through calcination under conditions of temperature equal to 450ºC and atmospheric air. The characterization techniques used in this work were: FTIR, DRX, MEV, particle size analysis and zeta potential. The photocatalysis for the AZN dye was investigated through the application of a factorial experimental design 2⁴, aiming at the best experimental conditions and finally applying them in another AMN industrial dye. The investigated AZN concentrations were 10 ppm and 30 ppm, the composites were synthesized using 10 and 30% (m/m) titanium dioxide in palygorskite, the two pH values were 2 and 6 and the light intensities were powers 9 and 18W are used. Tests performed at: pH 2.0; TiP30 composite; 18W power and 10 ppm of dye, showed 100% removal of both dyes in 90 min. The decolorization process followed the pseudo-first order kinetic model and the apparent constant (k_app) was 0.0216 min^-1 and 0.0193 min^-1 for the AZN and AMN dyes, respectively. The results of the final treatment cost for the tests were feasible in terms of efficiency and economy. Since, under the best parameters studied, the photocatalysis of AZN and AMN had an energy consumption of 0.135 kWh / dm³ and a final cost of R$ 0.0895.

BANKING MEMBERS:
Externo à Instituição - JOÃO SAMMY NERY DE SOUZA - UFPI
Presidente - 1645110 - CARLOS ALBERTO MARTINEZ HUITLE
Interno - 348475 - DJALMA RIBEIRO DA SILVA
Externa ao Programa - 1412709 - NEDJA SUELY FERNANDES