Banca de DEFESA: DALILA APARECIDA FARIA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : DALILA APARECIDA FARIA
DATE: 28/04/2023
TIME: 14:00
LOCAL: Campus VI
TITLE:

SYNTHESIS AND CHARACTERIZATION OF g-C3N4 AND ITS APPLICATION AS A FIRE RETARDANT IN VEGETABLE FUEL

KEY WORDS:

Forest Fires; Fire retardants; g-C3N4; NH4H2PO4; Burn Test.

PAGES: 60
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Inorgânica
SUMMARY:

In this work g-C3N4 (CN) was tested as a fire retardant, for application in forest fires. For this, CN was synthesized by the melamine thermal polycondensation method and its characterization was performed by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), absorption spectroscopy in the Fourier Transform infrared region (FT-IV), X-ray photoelectron excited spectroscopy (XPS), N2 adsorption/desorption isotherm and elemental analysis (CHN). The fire retardant property of CN was verified with burn tests using hay grass as fuel. The tests showed that g-C3N4 conferred fire retardant properties to the plant material, prolonging the burning time and decreasing the mass of residual fuel. These experiments also revealed that the fire retardancy of CN is more expressive in the increase of the burning time, than in the increase of the residual mass. The mixture of CN and NH4H2PO4 (MAP) was also evaluated in burning tests, obtaining as a result, the improvement of the fire retardant efficiency, in relation to pure CN. These data revealed the existence of a synergistic effect between CN and MAP, so that MAP promoted carbonization, increasing the residual mass, while CN slowed down the burning process. Thermal decomposition of CN was studied by FT-IV and TG (thermogravimetric analysis). The results showed that the material has high thermal stability, which gives it the property of forming a physical barrier during heating. In addition, it was noted that, given the increase in temperature, CN releases water molecules adsorbed in its porous structure, promoting cooling. This cooling can alter the pyrolysis process of the plant material, increasing the residual mass. In addition, CN decomposition can release diluent gases, reducing the concentration of combustible gases. With this information, a fire retardant mechanism for g-C3N4 was proposed.

COMMITTEE MEMBERS:
Presidente - EUDES LORENCON
Interna - RAQUEL VIEIRA MAMBRINI
Interna - IVINA PAULA DE SOUZA
Interno - EMERSON FERNANDES PEDROSO