Produção de bioquerosene e hidrocarbonetos renováveis por meio da pirólise do óleo de coco utilizando catalisadores H-Beta e SBA-15 impregnados com Ni

Abstract

In the present work, a study of the pyrolysis process of coconut oil (Coco Nucifera), using the Ni catalyst on SBA-15 supports and on H-Beta zeolite, to produce aviation biokerosene was carried out. The catalysts were calcified and characterized by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy coupled to the Energy Dispersive Spectrometer (SEM/EDS). The SBA-15 was obtained with hexagonal ordering and symmetry, the thermal activation of H-Beta did not compromise its structure and the impregnations with the metal resulted in the targeted percentages and its presence did not change the morphology and structure of the supports. The thermal and kinetic studies were performed using the Thermogravimetric Analysis technique (TGA/DTG). Then, Gas Chromatography coupled with Mass Spectrometry (GC/MS) was used to analyze the biooil samples. In order to better understand the behavior of this process, heating rates of 5, 15 and 20 °C/min were used in the experiments, in the temperature range between 30 and 600 °C and 10% of catalyst. In general, the increase in the heating rate provided an increase in the temperature range, maximum temperature and a decrease in mass loss. In the kinetic study, lower heating rates produced higher conversions and the KissingerAkahira-Sunose (KAS) model was better suited to the process. Conversions greater than 90% were verified. The catalyst with the highest catalytic activity was H-Beta 5% Ni for the entire process with an average Ea of 318.06 kJ/mol for the KAS model. The influence of nickel metal on the reaction was also analyzed using SBA-15 and H-Beta as catalytic supports. Samples were characterized by CG/MS. In thermal pyrolysis without Ni, biooil yields of 69.76% were achieved. Using the H-Beta 5% Ni catalyst, 77.83% of bio-oil and 1.80% of water were reached, showing that Ni provided a certain deoxygenation of the bio-oil. The catalysts SBA-15 1% Ni, SBA-15 5% Ni, H-Beta 1% Ni and H-Beta 5% Ni produced hydrocarbons in the range of C11-C16 kerosene at 73.73%, 73.17%, 78 .08% and 2.77%, respectively. Concluding that the first 3 were selective in the kerosene range.