Banca de QUALIFICAÇÃO: RAISSA DOS NAVEGANTES DA SILVA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : RAISSA DOS NAVEGANTES DA SILVA
DATE: 26/08/2025
TIME: 14:00
LOCAL: https://meet.google.com/ckm-mtdt-enb
TITLE:

Obtaining and characterizing soda/AQ lignin obtained from different biomasses.

KEY WORDS:

Lignocellulosic biomass, Lignin, Soda/anthraquinone, Autoclave, Extraction.

PAGES: 73
BIG AREA: Outra
AREA: Ciências Ambientais
SUMMARY:

Lignocellulosic biomass, composed of cellulose, hemicellulose, and lignin, is a renewable and promising raw material for the development of sustainable chemical products. Among its components, lignin stands out for its potential in industrial applications, although its utilization still faces challenges related to extraction and purity. This study aimed to extract and characterize lignins obtained from wood pallets, cashew prunings, and sisal fibers using an adapted soda/anthraquinone method with autoclave heating. Initially, the biomasses were characterized in terms of moisture, ash, total extractives, soluble and insoluble lignin, holocellulose, alpha-cellulose, hemicellulose, and elemental composition. Lignin extraction was carried out under different operational conditions, focusing on yield optimization. The highest efficiency was obtained from cashew prunings, reaching 56.81% under optimized conditions (2 mol·L⁻¹ NaOH, 2 h extraction, 24 h pre-soaking, and presence of anthraquinone). Wood pallets and sisal also showed good yields, with 26.60% and 24.78%, respectively. The extracted lignins were characterized by TG/DTG, DSC, FTIR, UV-Vis, and elemental analysis, revealing structural differences among the biomasses, particularly in thermal stability and condensation degree. The use of an autoclave as an extraction reactor proved to be efficient, simple, and reproducible, with potential for laboratory-scale and industrial applications. The results indicate that the proposed method is viable for the valorization of different lignocellulosic residues and may be further optimized for future technological applications or patent protection.

BANKING MEMBERS:
Externo à Instituição - DANIEL FREITAS FREIRE MARTINS - UFERSA
Interno - 13136 - LEANDRO BEZERRA DE LIMA
Presidente - 12281 - VINICIUS PATRICIO SANTOS CALDEIRA