Banca de DEFESA: MARIA JOSÉ GOMES DE ARAÚJO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : MARIA JOSÉ GOMES DE ARAÚJO
DATA : 26/07/2018
HORA: 14:00
LOCAL: Auditório do NUPPRAR
TÍTULO:

CARBON FOAMS: SYNTHESIS, CAHARACTERIZATION AND APPLICATION.

PALAVRAS-CHAVES:

Carbon foams, blowing agentes, glycerol, texture propierties, removal CO2

PÁGINAS: 105
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
ESPECIALIDADE: Cerâmicos
RESUMO:

The advancement of science and the search for new materials has been outstanding in recent years. Among these new materials are the carbon foams porous structure materials consisting mainly of macropores, which present high specific area, light weight, thermal and electrical conductivity, high thermal stability, being applied as adsorbents, electrodes, supports for catalysts, thermal insulation at high temperatures and others. Several methods and raw materials have been used to synthesize carbon foams, these include petroleum sources and derivatives, but the limit and scarcity of these materials makes it necessary to search for raw materials from renewable sources or biomass. As a result, this research aimed to synthesize carbon foams using sucrose as the carbon source and the aluminum, iron and silver nitrates as blowing agents, besides these, carbon foams using montmorillonite as reinforcing agent were also produced. Finally, we studied the substitution of the traditional sucrose carbon source for glycerol (biomass) and the materials were applied to remove CO2 from the environment. Therefore, a methodology known for obtaining these materials called blowing of the carbon precursor through the addition of chemical agents was adopted. Morphology, structure, texture properties, mechanical strength and CO2 adsorption capacity at 35 ° C were evaluated in the obtained samples. It is observed that nitrates of iron, silver and aluminum were efficient as blowing agents in the production of carbon foams, contributing to the structure of interconnected pores and high porosity in the 90% range, the samples have a good BET specific surface, especially were synthesized with aluminum nitrate (EsAl) and iron nitrate (EsFe) with values of 600 and 380 m2/g, respectively. The addition of the reinforcing agent (montimorillonite) in the production of carbon foams shows a trend in improving the mechanical strength of the EsAlAr foams (2.28 MPa) attributed good dispersion of the reinforcement on the surface of the samples. Efficient substitution of up to 50% sucrose content by glycerol in the synthesis of carbon foams, shows an increase in the BET specific surface as the proportion of glycerol increases in the foams. All samples synthesized with iron nitrate present a more ordered structure with larger domain size. The capture of CO2 at 35 ° C is efficient in the foams obtained, highlighting in the samples synthesized with aluminum nitrate (EsAl) and in samples with glycerol proportions of 10 and 30% (EsGl10 and EsGl30) with CO2 capture value of 5.3 mmol.g-1.

MEMBROS DA BANCA:
Externo à Instituição - DALVA LÚCIA ARAÚJO FARIA - USP
Externo à Instituição - EDUARDO RIGOTI - UFRN
Externo à Instituição - JHONNY VILLARROEL ROCHA - NOVA
Externo à Instituição - MANUEL KARIM SAPAG - UNSL
Interno - 1350249 - RUBENS MARIBONDO DO NASCIMENTO
Presidente - 1308577 - SIBELE BERENICE CASTELLA PERGHER