Banca de DEFESA: AMANDA MEDEIROS DE AZEVEDO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : AMANDA MEDEIROS DE AZEVEDO
DATE: 23/10/2023
TIME: 09:00
LOCAL: Auditório do NUPPRAR
TITLE:

Photocatalytic decarboxylation of fatty acids for production of drop-in biofuels.

KEY WORDS:

biofuel; photocatalysis; decarboxylation; fatty acids

PAGES: 80
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Orgânica
SPECIALTY: Síntese Orgânica
SUMMARY:

The growing concern about the progression of the effects of global warming caused by greenhouse gas emissions (GHGs) over the years has sparked interest in diversifying the energy matrix. In this context, there has been an increase in the demand to produce drop-in biofuels, chemically identical to fossil fuels, to reduce dependence on non-renewable resources and mitigate CO₂ emissions. To form a mixture of renewable hydrocarbons compatible with engine structures, the biomass to be used needs to undergo deoxygenation processes, such as thermo-catalytic ones. However, existing methodologies have some operational limitations such as high temperatures, high hydrogen gas pressures, and the need for specific reactors. In this sense, the present work proposes the development of a selective photocatalytic method for deoxygenating fatty acids from vegetable oils under mild conditions, using an organic photocatalyst, at room temperature, in a metal-free process without the use of hydrogen gas. After the optimization of the reaction conditions carried out for a model compound, lauric acid (C12:0), a major component of some vegetable oils, yields of up to 80% were obtained for the formation of undecane. The evaluated parameters included the photocatalyst, hydrogen transfer agent, base, their respective stoichiometries, reaction concentration, light source, reaction time, as well as the performance of control experiments. Subsequently, the reaction scope was analyzed by applying the methodology to other pure fatty acids (capric, myristic, palmitic, stearic, oleic, and linoleic acids), obtaining yields of up to 60% for these species. Furthermore, to assess the robustness of the method, the decarboxylation of bio-derived fatty acids obtained from the hydrolysis of commercial Licuri oil was evaluated, resulting in a conversion of over 90% with high selectivity for the respective hydrocarbons. Thus, this new method emerges as a viable alternative to existing deoxygenation processes for producing mild drop-in biofuels with highly selective formation of Cn-1 hydrocarbons.

COMMITTEE MEMBERS:
Presidente - 2140818 - AMANDA DUARTE GONDIM
Interno - 1645110 - CARLOS ALBERTO MARTINEZ HUITLE
Externa ao Programa - 2140775 - LIVIA NUNES CAVALCANTI - nullExterna à Instituição - NATALY ALBUQUERQUE DOS SANTOS - UFPB