Banca de QUALIFICAÇÃO: LAISLA CAROLINA ANDRADE FERREIRA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : LAISLA CAROLINA ANDRADE FERREIRA
DATE: 26/07/2024
TIME: 09:00
LOCAL: Google Meet
TITLE:

USE OF SUGAR AND ALCOHOL INDUSTRY WASTE IN THE PRODUCTION OF HYDROCHAR VIA HYDROTHERMAL CARBONIZATION (HTC) FOR USE IN SUSTAINABLE SYSTEMS OF AGRICULTURE

KEY WORDS:

Hydrochar; organic agriculture; environmental technologies; organic matter

PAGES: 44
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Analítica
SPECIALTY: Análise de Traços e Química Ambiental
SUMMARY:

Brazil is the leading producer of sugarcane and faces environmental challenges due to the large volume of agro-industrial residues generated (e.g., straw, bagasse, and vinasse). In this context, hydrothermal carbonization (HTC) emerges as a promising technology for treating and converting this biomass into hydrochar, a high-value agricultural input. In this study, sugarcane bagasse was subjected to HTC under different experimental conditions, varying preparation time (10, 12, and 14 h), temperature (180, 190, and 200°C), and reaction medium (H₂O or 0.1 mol L^–1 HNO₃). The hydrochars were characterized for yield, Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscopy (SEM). The results showed lower yields in reactions conducted at higher temperatures, longer times, and with the use of HNO₃(48.72-51.09%). In contrast, reactions using H₂O showed significantly higher yields (72.27-74.18%). In FTIR, the band at 3342 cm^–1 decreased in samples A/14/200 and W/14/200, indicating the carbonization of cellulose in the residues. A lower intensity was also observed in the range of 1800 to 1600 cm^–1, associated with C=O groups, mainly from hemicellulose and lignin, which were reduced during hydrothermal carbonization. This reduction was more pronounced under severe conditions, such as in W/14/200 and A/14/200, due to the thermochemical conversion of the biomass. In SEM, HTC modified the structure of the sugarcane bagasse, promoting the formation of grooves in the fibers and reducing the interstitial material between the cavities. The action of HTC was more intense in reactions with HNO₃ due to the action of subcritical water vapor associated with oxidation caused by the acid. The micrographs showed that the morphological structure of the hydrochars was more carbonized under more severe preparation conditions. The results obtained so far indicate the feasibility of preparing hydrochars from sugarcane residues, recycling a material that would be wasted or underutilized, and producing a potential low-cost agricultural input. Future analyses will be conducted to evaluate the potential of hydrochars in more modern and sustainable agricultural practices, reinforcing their applicability and benefits for agriculture.

COMMITTEE MEMBERS:
Presidente - RAMOM RACHIDE NUNES
Interno - JANDYSON MACHADO SANTOS
Interno - MARCILIO MARTINS DE MORAES
Externo à Instituição - WANDER GUSTAVO BOTERO - UFAL