Gondim, Amanda DuarteFerreira, Isabelle Mariane de Lima2023-12-202023-12-202023-07-26FERREIRA, Isabelle Mariane de Lima. Produção de hidrocarbonetos renováveis a partir da pirólise catalítica da microalga Monoraphidium sp. com material microporoso (HZSM-5). Orientadora: Dra. Amanda Duarte Gondim. 2023. 148f. Tese (Doutorado em Química) - Centro de Ciências Exatas e da Terra, Universidade Federal do Rio Grande do Norte, Natal, 2023.https://repositorio.ufrn.br/handle/123456789/56588The energetic potential of microalgae of the species Monoraphidium sp. It was explored as a raw material for the production of renewable hydrocarbons. For this, the biomass was subjected to physicochemical pre-treatments with the aim of facilitating the intracellular access of microalgae. The renewable hydrocarbons from the treated biomass were obtained through thermal and catalytic pyrolysis processes in the presence of the HZSM5 catalyst. The HZSM-5 zeolite was synthesized and characterized by X-ray diffraction (XRD), surface area analysis (BET), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and Determination of acidity by the base adsorption method (n-butylamine). XRD analyzes confirmed the formation of the MFI-type crystalline structure, with standards similar to those defined by the International Zeolite Association (IZA). The acidity analysis showed the presence of acidic sites in the zeolite necessary for reactions in catalytic pyrolysis. The kinetic parameters involved in the pyrolysis reactions of microalgae biomass were estimated through the development of the Ozawa-Flynn-Wall (FWO) and Kissinger-Akahira-Sunose (KAS) models, with the aid of thermogravimetric analysis (TGA/DTG) in the ratios heating 10, 20, 30 and 40 °C/min. In which, it was evident that the two models generated accurate kinetic data that reflect the thermal conversion of the biomass, resulting in average activation energy values of 104.2 and 122.2 kJ/mol (FWO) and 99.96 and 118, 2 kJ/mol (KAS). Pyrolysis led to the formation of the liquid product, bio-oil, which was characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatography coupled with a mass spectrometry detector (GC-MS). The chemical composition by GC-MS showed that the bio-oils produced have a variety of compounds, and the bio-oils generated in thermocatalytic pyrolysis showed a reduction in the distribution of oxygenates and an increase in hydrocarbons, as an indication of the deoxygenation reactions promoted by zeolite HZSM-5. Furthermore, they are sources of renewable hydrocarbons that can be precursors to biofuels, as they contain hydrocarbons in the C6-C20 range, which includes the range of gasoline, diesel and aviation kerosene.Acesso AbertoQuímicaMicroalgasMonoraphidium sp.Hidrocarbonetos renováveisPiróliseHZSM-5doctoralThesisCNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA