Banca de DEFESA: JÚLIO DE ANDRADE OLIVEIRA MARQUES

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : JÚLIO DE ANDRADE OLIVEIRA MARQUES
DATE: 27/02/2026
TIME: 10:00
LOCAL: LABTAM
TITLE:

Valorization of Anadenanthera colubrina through a Cascading Biorefinery Approach: From post-extraction residues to Renewable Platform Chemicals

KEY WORDS:

Analytical pyrolysis; Bioproducts; Biorefinery; Bio-oil; Residual biomass

PAGES: 82
BIG AREA: Ciências Agrárias
AREA: Recursos Florestais e Engenharia Florestal
SUBÁREA: Energia de Biomassa Florestal
SUMMARY:

The integrated valorization of lignocellulosic biomass through cascade biorefinery approaches has been widely discussed as a sustainable alternative to produce bioproducts and bioenergy. However, studies that comprehensively evaluate the characterization of extracted compounds and the impact of their removal on the structure of the remaining solid fraction and the selectivity of pyrolysis products are still scarce, especially for native species of the Caatinga biome. In this context, this study investigated the conversion of Anadenanthera colubrina bark through sequential extraction of tannins and lignin, followed by non-catalytic flash pyrolysis, with the aim of elucidating the chemical evolution of the raw biomass to the final byproduct. The biomass was subjected to aqueous extraction, resulting in tannins and byproduct 1, followed by alkaline extraction, resulting in a recovered lignin fraction and byproduct 2. The solid samples (raw biomass, byproduct 1, and byproduct 2) underwent comprehensive physicochemical characterization, as well as Py-GC/MS analysis, with physicochemical parameters determined using complementary analytical approaches to increase methodological robustness and reproducibility, while the tannin and lignin extracts were evaluated in terms of thermal behavior, elemental composition, and spectroscopic techniques (UV-Vis and FTIR). The progressive removal of tannins and lignin promoted the transition of the raw biomass to byproduct 2, resulting in a material enriched in cellulose and hemicellulose, associated with increased structural homogeneity. Furthermore, an increase in the content of ash rich in CaO and K₂O was observed, which may indicate catalytic effects during the thermochemical conversion. Pyrolysis of byproduct 2 at 500 °C revealed a reduction in phenolic compounds (≈46 → 25%) and nitrogenous compounds (≈10.5 → 3.8%) compared to raw biomass, with a predominant decrease in p-hydroxyphenyl derivatives and a significant increase in ketones derived from carbohydrate degradation. These modifications indicate the formation of more stable vapors and bio-oils with a more suitable chemical composition. Therefore, integrating tannin and lignin recovery with the thermochemical conversion of the remaining byproduct represents an effective strategy to maximize valorization, contributing to the development of sustainable biorefineries aligned with SDGs 7, 9, 12, and 13, as well as supporting the principles of the circular economy and green chemistry practices.

COMMITTEE MEMBERS:
Presidente - 1979301 - RENATA MARTINS BRAGA
Interna - 2326526 - TATIANE KELLY BARBOSA DE AZEVEDO CARNAVAL
Externa à Instituição - GISLANE PINHO DE OLIVEIRA - UFMA
Externo à Instituição - TIAGO ROBERTO DA COSTA - IFRN