Banca de DEFESA: YURI LEANDRO RODRIGUES LOPES FERNANDES

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : YURI LEANDRO RODRIGUES LOPES FERNANDES
DATE: 13/04/2022
TIME: 07:30
LOCAL: SalaVirtual
TITLE:

Study, preparation and characterization of Diatomite/Nb2O5/TiO2 porous nanocomposites for the treatment of contaminated water

KEY WORDS:

 Keywords: Diatomite. Titanium dioxide. Niobium pentoxide. Filtration.

PAGES: 90
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
SPECIALTY: Cerâmicos
SUMMARY:

The emerging need for more efficient water treatment methods to remedy the scarcity of this limited natural resource has become a problem beyond the scientific character: it covers ethical, economic and social issues. The advancement of understanding about the mechanisms of filtration and treatment of contaminated water by porous matrix composites, such as diatomite, stimulated the development of this work. In this study, the white diatomite ceramic powder was used to manufacture porous composites incorporated by submicrometric particles of niobium pentoxide and titanium dioxide nanoparticles, through the Tape Casting forming technique: originating 4 ceramic-polymer tapes of distinct compositions. Finally, six-layer laminates were thermo-pressed, calcined and sintered. The ceramic powders were evaluated by laser diffraction particulometry, field emission scanning electron microscopy (SEM-FEG), x-ray diffraction (XRD) and x-ray fluorescence (XRF). The thermal behavior of the tapes was determined by thermogravimetric analysis (TG). Aiming to verify the effect of the production route used on the morphological characteristics, the composition of crystalline phases, and the flexural strength, the sintered composites, called pellets, were characterized by XRD, SEM-FEG, and a three- point bending test. It was possible to verify, therefore, the efficiency of the production route in obtaining porous composites sintered at 1200 ºC with monolithic character. Furthermore, the crystalline structures and final phase composition was determined, observing the evolution of the crystallinity of the diatomite particles and the compositional impact on the phase transformation of the titanium dioxide. The bending test allowed the evaluation of the mechanical behavior of the pellets as a function of the composition used, verifying its suitability for application as a ceramic filter.

BANKING MEMBERS:
Presidente - 345842 - UILAME UMBELINO GOMES
Interno - 1300987 - CARLOS ALBERTO PASKOCIMAS
Externo ao Programa - 2414250 - MEYSAM MASHHADIKARIMI
Externa à Instituição - ARIADNE DE SOUZA SILVA