Banca de QUALIFICAÇÃO: MÁRCIO CLEIVO DE MORAIS SOUZA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : MÁRCIO CLEIVO DE MORAIS SOUZA
DATE: 15/05/2023
TIME: 09:00
LOCAL: videoconferência
TITLE:

Biohydrocarbons from catalytic processes using micro and mesoporous catalysts with Co and Mo

KEY WORDS:

Sunflower Oil; MCM-41; HZSM-5; Pyrolysis; Kinetic Study; Biohydrocarbons

PAGES: 156
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Físico-Química
SPECIALTY: Cinética Química e Catálise
SUMMARY:

The search for new sources of renewable energy is growing all over the world, this growth is due to the environmental problems caused by the excessive use of fossil fuels that cause a series of damages to the environment. Faced with this problem, this work aims to evaluate the use of microporous catalysts ZSM-5 and mesoporous MCM-41 impregnated with cobalt and molybdenum metals in the production of biohydrocarbons using sunflower oil via rapid pyrolysis. All catalytic materials were characterized via X-Ray Diffraction (XRD), X-Ray Fluorescence (FRX) and Fourier Transform Infrared Spectroscopy (FTIR) analyses, these analyzes indicated that they were excellently formed and their structures matched remained intact after the impregnation of the metals, while the sunflower oil was characterized via physicochemical analyses, such as acid number, peroxide, saponification, refraction, free fatty acids and density. Then, a thermal and kinetic study of the degradation reaction of sunflower oil was carried out using micro and mesoporous catalysts, through thermal analysis, based on the free kinetic models proposed by Ozawa Flynn Wall (OFW) and Kissinger Akahira Sunose (KAS) . Thermogravimetric analyzes (TGA) of sunflower oil and sunflower oil with catalysts were performed at heating rates (β) of 10, 20 and 30ºC/min, then the data were plotted and evaluated according to the proposed models, thus obtaining calculate the activation energies (Ea) for the conversion rates (α) 5, 10, 20, 30, 40, 50, 60, 70, 80 and 90%. The results indicated that all catalysts used showed catalytic activity, especially Mo/MCM-41 and Mo/HZSM-5, which showed the greatest reductions in activation energies (Ea). Both in the OFW model and in the KAS, the methodologies used proved to be adequate (R2 > 0.9). The thermodynamic parameters (A, ΔH, ΔG and ΔS) were also calculated in the reactions of thermal and thermocatalytic degradation of sunflower oil, which we can highlight ΔH>0, indicating that it is an endothermic reaction and ΔG>0 corresponding to a non-spontaneous reaction. These kinetic study results are also used as a basis for thermal and catalytic pyrolysis reactions. In the pyrolysis process, the percentages of hydrocarbons formed were as follows: In thermal pyrolysis, 16% was obtained, in catalytic pyrolysis, this percentage of hydrocarbons was 28% (MCM-41), 16% (Mo/MCM-41), 21% (Co/MCM-41) and 45% (Co-Mo/MCM-41). Of these percentages of hydrocarbons formed, in thermal pyrolysis 53.23% are in the Biokerosene range and 46.77% in the Green Diesel range, whereas in catalytic pyrolysis, the presence of catalysts favored the deoxygenation of the pyrolysis products of oil sunflower by decarbonylation reaction, being for (MCM-41) 8.57% in the gasoline range, 29.37% in the biokerosene range and 62.06% in the green diesel range, for (Mo/MCM-41) 24.55% in the biokerosene range and 75.45% in the green diesel range, for (Co/MCM-41) 27.49% in the biokerosene range and 72.51% in the green diesel range, for (Co- Mo/MCM-41) 19.41% in the biokerosene range and 80.59% in the green diesel range.

COMMITTEE MEMBERS:
Presidente - 2140818 - AMANDA DUARTE GONDIM
Externa à Instituição - ANNE GABRIELLA DIAS SANTOS - UERN
Interno - 350509 - ANTONIO SOUZA DE ARAUJO
Externo à Instituição - JOAO PAULO DA COSTA EVANGELISTA - UFRN
Externa à Instituição - MARIA JOSE FONSECA COSTA - UFRN