Banca de QUALIFICAÇÃO: LARISSA NASCIMENTO LÔBO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : LARISSA NASCIMENTO LÔBO
DATE: 29/09/2023
TIME: 14:00
LOCAL: Defesa na forma remota pela plataforma google meet
TITLE:

OBTAINING NANOLIGNIN FROM THE SHELL AND FIBER OF GREEN COCONUT (Cocos sp.)

KEY WORDS:

Green coconut, Lignin, Acetosolv pulping, Ultrasonication

PAGES: 50
BIG AREA: Engenharias
AREA: Engenharia Química
SUBÁREA: Processos Industriais de Engenharia Química
SPECIALTY: Processos Bioquímicos
SUMMARY:

With the growing need to replace non-renewable resources, especially petroleum derivatives, due to population growth and global environmental concerns, lignocellulosic biomass, rich in macromolecules such as lignin, appears as a promising alternative. Lignin, the second most abundant biopolymer in nature, plays vital roles in plants and has attractive properties for industrial applications. Several lignin extraction methods are mentioned, with acetosolv pulping highlighted for its effectiveness and sustainability. This research aims to obtain nanolignin from lignin from the shell and fiber of green coconuts (Cocos nucifera) using the acetosolve method. The research began with the collection of green coconut waste and its preparation to obtain flour. The flour was then characterized for total extractives, ash content, lignin, moisture, holocellulose, alphacellulose and hemicellulose. Acetosolv pulping will be carried out in two stages, varying temperature conditions and presence of extractives. Lignin will be obtained by precipitation and subsequently characterized. The nanolignin will be obtained through ultrasonication and will be analyzed for zeta potential and particle size distribution. The procedure aims to contribute to sustainability, using waste and valuing natural resources. The dissertation covered five main stages. The physical-chemical characterization of the green coconut flour revealed extractive contents between 2.6 and 19.26%, moisture from 9.22 to 10.5%, ash from 0.98 to 5.12%, and proteins between 3 .56 to 8.27%. Analysis of the primary components of coconut husk and fiber demonstrated a lignin content of 40%, indicating a high concentration of this compound compared to other biomasses. In relation to cellulose and hemicellulose, the values obtained were 15.90% and 15.86%, respectively, falling within the ranges found in other studies. These results indicate that green coconut husk and fiber are rich sources of lignin compared to other lignocellulosic biomasses. The variation in cellulose and hemicellulose contents can be attributed to differences in cultivars, growing conditions and geographic location. When evaluating the data with previous references, it was found that the results obtained in this dissertation align with the trends presented in previous studies on secondary and primary components of green coconut. Therefore, the data presented here contributes to the understanding of the chemical composition of green coconut husk and fiber, providing valuable information for its potential application in industrial and sustainable processes. The next stages of the research involve the extraction of lignin using the acetosolv method, exploring temperature variations (80, 100 and 120°C) and the presence of extractives in the biomass. A thorough evaluation of these parameters will be carried out to determine the ideal extraction conditions. Next, nanolignin will be produced through ultrasonication. The characteristics of the products obtained will be analyzed, considering the influence of temperature and the presence of extractives. Finally, the nanolignin in the best condition will be subjected to a comprehensive qualitative and quantitative characterization. The schedule foresees the completion of these stages over the next few months, with a balanced distribution of efforts between activities, ensuring an efficient and coherent progression of the project.

COMMITTEE MEMBERS:
Presidente - 1456420 - RENATA MARIA ROSAS GARCIA ALMEIDA
Interno(a) - 3081569 - CARLOS EDUARDO DE FARIAS SILVA
Externo(a) à Instituição - FRANCINE PIMENTEL DE ANDRADE - UFAL
Externo(a) à Instituição - MÁRCIA ANDRÉA GOMES - IFAL