Hidrotratamento do óleo residual para produção de biocombustíveis

Abstract

Due to the problems caused by fossil fuels on the planet and their possible depletion, thermochemical conversion routes from biomass become alternative paths for the production of biofuels. Within biomass, residual oil stands out because it does not compete directly with the food production chain and also because it transforms a material with low added value into a product with high added value. Thermal pyrolysis can be used to convert these residues, mainly because it is capable of converting the fatty acids present in products in the hydrocarbon range. Linked to the desired products, fast pyrolysis can be used, as its main products are liquid fractions of bio-oil. The present work proposes carrying out the residual oil hydrotreatment process through thermal pyrolysis reactions to convert the residual oil into bio-oil, for subsequent treatment, using techniques such as Pd/C, Fe-Co/ZSM-5, Fe /ZSM-5 in different proportions, supporting mild hydrogenation reactions, reducing the amount of oxygenates present in the bio-oil. The results were characterized by X-ray Diffraction (XRD), Infrared Spectroscopy (FTIR) and Thermogravimetry (TG) for the purpose of thermal study after acidity test. The residual oil was characterized by quantitative and qualitative techniques such as acidity index (AI), saponification index (SI), consistency, density and free fatty acid content (FFA). After the pyrolysis process, the bio-oil was characterized by specific density, thermogravimetry (TG), and gas chromatography coupled to mass spectrometry (GC/MS), after the hydrogenation process. Finally, the efficiency of the hydrogenation process was verified with different trends leading to the percentage of oxygenates up to 58%, in addition to the selective conversion into hydrocarbons, where Fe-Co/ZSM-5 presented a better yield for hydrocarbons than the expected Pd/C.