Amanda Duarte Gondim

Thermal and catalytic pyrolysis of vacuum gas oil using HZSM-5: TG and PY-CG/MS study

ABSTRACT The zeolite HZSM-5, was synthesized in the absence of an organic template. The characterization of zeolite HZSM-5 was performed by X-ray diffraction, N2 adsorption/desorption isotherms and scanning electron microscopy. For catalytic tests, applying the free kinetic model, it was observed that the activation energy for the pyrolysis of pure VGO was of 82 kJ mol−1 and for VGO/HZSM-5, the value decreased to approximately 60 kJ mol−1, demonstrating the effectiveness of the acid sites effect of zeolite ZSM-5 for the VGO pyrolysis resulting in production of gas, gasoline and diesel.

Kinetic study on the thermal degradation of heavy oil in presence of SBA-15 containing aluminum and cerium

ABSTRACT In research for materials that can be applied in processing heavy oil (petroleum), this work proposes to synthesize mesoporous heterogeneous catalysts, type SBA-15, with the addition of cerium metal and aluminum. These catalysts were characterized by X-ray diffraction, scanning electron micrographs coupled to energy dispersive spectrometry, spectroscopy in the infrared region by Fourier transform, N2 adsorption and desorption and thermal analysis-thermogravimetry. Thermal tests were performed to evaluate the thermal and catalytic degradation process with a sample of heavy oil (°API = 14). Through the non-isothermal kinetic model of Ozawa Flynn Wall (OFW) some parameters for determining the apparent activation energy of decomposition were obtained. The petroleum with 12% of Ce5Al50SBA-15 showed a catalytic activity for this material. It has been seen that there was a decrease in the Ea in model free of the order from 89.0 to 104.9 kJ mol−1 in α = 50% ± 10%, and it was repeated from the first percentage until the last showing performance of Ce5Al50SBA-15 as a catalyst.

Flow properties of biodiesel: correlation between TMDSC and dynamic viscosity

Sustainable and renewable energy has become more attractive due to its environmental benefits. Among these alternative sources, biodegradable and low emission biodiesels have been gaining attention as compared to diesel. However, their performance at low temperatures affects their commercial viability, because of engine performance problems, and when starting. Cold Filter Plugging Point, Pour Point, and Cloud Point are employed to predict the limits of operability for biodiesel. However, dynamic viscosity and TM-DSC methods are also useful to assess these properties and can be correlated. Viscosity curves were obtained, and TM-DSC revealed that the start temperature (transition liquid–solid) exhibits an increase in flow resistance for soybean, colza, sunflower, corn, and babassu oil biodiesels. The nucleation processes which occur during cooling are unique for each type of biodiesel due to the presence of different ester compositions and the values for viscosity and flow at low temperatures varied accordingly.