Banca de QUALIFICAÇÃO: BRENDA PALHARES DOS REIS VIEIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : BRENDA PALHARES DOS REIS VIEIRA
DATE: 23/08/2023
TIME: 09:00
LOCAL: Auditório do Campus VI
TITLE:

CARBON DOTS FROM SUGARCANE BAGASSE WASTE VIA HYDROTHERMAL CARBONIZATION: Synthesis, Characterization and Application

KEY WORDS:

Carbon dots; hydrothermal carbonization; biomass, sugarcane bagasse; photocatalysis.

PAGES: 65
BIG AREA: Outra
AREA: Multidisciplinar
SUMMARY:

Sugarcane bagasse is an abundant residue from the sugarcane industry, being mostly used as fuel in the mills. However, the conversion of this biomass into high value-added products has become very promising, such as the synthesis of carbon quantum dots (CD's). These can be synthesized by a green process, using hydrothermal carbonization. CD’s are nanoparticles that have distinct properties such as conductivity, large surface area, biocompatibility, low toxicity and fluorescence, properties that are responsible for numerous applications. Due to these characteristics, CD’s are good candidates as photocatalysts, which can be used in the degradation of organic contaminants in aqueous systems for wastewater treatment. Among these contaminants, azo dyes present complex molecules that are resistant to conventional treatment methods. Such as they come from textile, leather and paper industries, which have high demands. In this context, the synthesis of CD’s from sugarcane bagasse biomass via hydrothermal carbonization was carried out. Multivariate optimization was the statistical tool used to improve the synthesis conditions, so two 2^3-1 fractional factorial designs were constructed to screen variables. The experimental design allows the study of the interaction of the variables of influence on the response, and the potentiality of the use of CD's in the photodegradation of the dye, methyl orange, used as a model molecule. The CD's production parameters will be optimized in order to obtain the optimal conditions of photodegradation of the azo dye, with less use of experiments. The characteristics of the nanoparticles were initially evaluated by pH analysis, conductivity, Zeta potential, Fourier transform infrared spectroscopy (FTIR) and molecular absorption spectroscopy (UV-Vis), in addition to the characterizations that will be made, the quantum yield, fluorescence spectroscopy, transmission electron microscopy (TEM), Raman spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TG) and cytotoxicity test. The percussor biomass was also characterized by means of FTIR and TG.

COMMITTEE MEMBERS:
Presidente - EUDES LORENCON
Interna - ANGELA DE MELLO FERREIRA