Banca de DEFESA: ADISON PEREIRA DA SILVA JUNIOR

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ADISON PEREIRA DA SILVA JUNIOR
DATE: 29/12/2025
TIME: 09:30
LOCAL: MODO REMOTO
TITLE:

Synthesis of graphene aerogel from Calotropis procera biomass for potential application in CO2 capture.

KEY WORDS:

CO2 adsorption; Aerogel, Reduced graphene oxide; Calotropis procera; Functionalization.

 

PAGES: 75
BIG AREA: Engenharias
AREA: Engenharia Química
SUBÁREA: Tecnologia Química
SPECIALTY: Petróleo e Petroquímica
SUMMARY:

Mitigating carbon dioxide (CO2) emissions, the main greenhouse gas, is one of the most urgent environmental challenges today. Solid-gas adsorption using nanostructured porous materials emerges as an energy-efficient alternative to conventional liquid adsorption technologies. In this study, a reduced graphene aerogel (rGO) derived from Calotropis procera biomass (CP-rGO) was sustainably synthesized and functionalized with amines for selective CO2 capture. CP-rGO was obtained via pyrolysis, and the two-dimensional structure was obtained using a sodium alginate and agar-agar solution, followed by an ultrafreezing/lyophilization process. The material was characterized by XRD, FTIR, XPS, HRTEM, Raman spectroscopy, and SEM to validate its microstructural properties. XRD analysis revealed a broad peak centered at 24–26° (2θ), confirming the obtaining of rGO with disordered stacking. FTIR evidenced the effectiveness of thermal reduction, demonstrated by the attenuation of the band at ~1730 cm⁻¹ (carbonyl groups) and the preservation of the aromatic structure at ~1600 cm⁻¹ (C=C), fundamental for the stability of the adsorbent. Raman spectroscopy indicated an ID/IG ratio of 0.49, suggesting a partially ordered structure with structural defects beneficial for the anchoring of amine groups. SEM images confirmed the formation of a lamellar and highly porous morphology, derived from the original tubular structure of the Calotropis fiber. In application tests, surface functionalization with amines explored the chemical adsorption of CO2 at basic nitrogen sites, enhancing gas retention capacity compared to pure aerogel, which performs physical adsorption. The structural stability conferred by the biopolymers allowed for the regeneration of the material without significant loss of performance. The results show that the functionalized Calotropis aerogel combines the sustainability of residual biomass with the high performance required for carbon capture technologies, presenting itself as a promising and low-cost solution for atmospheric remediation.

COMMITTEE MEMBERS:
Interno - 347289 - AFONSO AVELINO DANTAS NETO
Interno - 2941160 - JOSE HERIBERTO OLIVEIRA DO NASCIMENTO
Interno - 1149554 - OSVALDO CHIAVONE FILHO
Externo à Instituição - RAFAEL BARBOSA RIOS