Banca de QUALIFICAÇÃO: ANTONIO ALEX DE LIMA SILVA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : ANTONIO ALEX DE LIMA SILVA
DATE: 28/07/2025
TIME: 14:00
LOCAL: Videoconferência
TITLE:

KINETIC EVALUATION OF THE THERMOCATALYTIC DEGRADATION OF MORINGA OLEIFERA OIL USING METAL OXIDES AND MODIFIED KIT-6.

KEY WORDS:

Non-conventional vegetable oils; Thermochemical conversion; Isoconversional methods; Nanocatalysts; Mesoporous materials

PAGES: 160
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Físico-Química
SPECIALTY: Cinética Química e Catálise
SUMMARY:

The growing global demand for renewable fuels, driven by the need to reduce greenhouse gas emissions and ensure energy security, has stimulated the development of new technologies for the production of advanced liquid biofuels. In this context, green hydrocarbons obtained through catalytic pyrolysis and hydrotreatment of vegetable oils have emerged as promising alternatives, standing out for their compatibility with existing refinery infrastructure and superior physicochemical properties compared to conventional biofuels. Among the potential feedstocks, Moringa oleifera Lam. oil is particularly noteworthy due to its high oleic acid content, low acidity, and excellent oxidative stability — attributes that favor efficient thermochemical conversion. Accordingly, this work aimed to evaluate the efficiency of mesoporous KIT-6-type catalysts, modified with molybdenum, calcium, and magnesium oxides, in the thermocatalytic degradation of moringa oil by determining the kinetic and thermodynamic parameters, as well as performing catalytic pyrolysis. Calcium and magnesium oxides were synthesized by chemical precipitation, molybdenum oxide by coprecipitation, and pure mesoporous KIT-6 material was also prepared. The oxides were impregnated onto the KIT-6 support via the solvent excess method. All materials were characterized by XRD, TGA/DTG, N₂ adsorption–desorption (BET), FTIR, SEM, and EDS analyses.The catalytic activity was assessed through the thermal degradation of moringa oil using thermogravimetric analysis at different heating rates. The kinetic data were processed using the isoconversional methods of Ozawa-Flynn-Wall (OFW) and Kissinger-Akahira-Sunose (KAS), enabling the determination of activation energies (Ea). The results demonstrated that both the isolated oxides and the impregnated materials exhibited catalytic activity in the process. Among them, magnesium oxide was particularly effective, promoting the most significant reduction in activation energy values. The KIT-6-supported catalysts showed enhanced thermal degradation efficiency of moringa oil compared to pure KIT-6, with reductions in both onset and maximum degradation temperatures. However, the Ea values for the impregnated materials remained higher than those observed for the thermal process and for the reactions conducted with isolated oxides, indicating that the nature and distribution of the active sites directly influence the energy required for the reaction. Therefore, the findings highlight the potential of the evaluated catalysts in the thermocatalytic degradation of moringa oil and emphasize the need for further studies through thermal and catalytic pyrolysis reactions. This next step is essential to determine the composition of the resulting products, validate the practical catalytic performance, and assess the selectivity toward the formation of green hydrocarbons for prospective energy and industrial applications.

COMMITTEE MEMBERS:
Externa à Instituição - ADRIANA PAULA BATISTA DOS SANTOS - UERN
Presidente - 2140818 - AMANDA DUARTE GONDIM
Externa à Instituição - ANNE GABRIELLA DIAS SANTOS CALDEIRA - UERN
Externa à Instituição - ARUZZA MABEL DE MORAIS ARAUJO - UFRN