Hidrólise do óleo do mesocarpo da macaúba (Acrocomia aculeata) utilizando catalisadores heterogêneos ácidos

Abstract

The growing global demand for energy and environmental concerns with the emission of greenhouse gases, such as carbon dioxide (CO2) and methane (CH4), which intensify global warming, associated with the reduction of fossil fuel reserves, has been causing a increase in research and development of technologies for the production of green fuels to replace the use of non-renewable fuels. This approach has gained more prominence in recent years with airlines setting a goal to reduce CO2 emissions through the use of blends containing 50% green aviation kerosene. Recently, GPCATT/UFU presented a technological contribution comprising a sequence of Hydrolysis-Reform-Hydrogenation-Deoxygenation processes that lead to the production of biofuels, but also to other products with high added value. In order to improve and scale up this technology, the main objective of this dissertation was to contribute to the study of the initial hydrolysis process of vegetable oils. Therefore, an attempt was made to evaluate the performance of different acid catalysts in the hydrolysis of macauba fruit mesocarp oil (OMM) – a highly promising oleaginous plant – in a batch reactor, comparing the respective catalytic performances. These catalysts were previously characterized by N2 Physisorption, X-Ray Diffraction (XRD), Temperature Programmed Ammonia Desorption (DTP-NH3) and X-Ray Fluorescence (XRD). The results of the characterizations showed that the presence of acid sites whose density and strength of the sites grew in the following order: This may explain the difference in the evolution of catalytic performance. Despite the presence of homogeneous reaction, all catalysts showed catalytic activity and selectivity to the formation of oleic acid (C18:1) and palmitic acid (C16:0). Then, a kinetic study was carried out using γ-Al2O3, which was the best catalyst, through experimental design. The apparent kinetic constant obtained at 250 °C (k_250) was approximately 30 times greater than that of the homogeneous reaction, with an apparent activation energy of 6.92 kJ∙mol-1.