IQ - TCC - Química do Petróleo

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Estudo da liquefação e co-liquefação hidrotérmica de microalgas e filtro de papel
(Universidade Federal do Rio Grande do Norte, 2026-05-22) Maciel, Lucas Vieira; Gondim, Amanda Duarte; Araújo, Aruzza Mabel de Morais; http://lattes.cnpq.br/1528626701927279; Cavalcanti, Lívia Nunes; Araújo, Aruzza Mabel de Morais; Monastirski, Amanda Menezes Caldas
This work studied the hydrothermal liquefaction (HTL) and co-hydrothermal liquefaction (Co-HTL) of the microalga Scenedesmus obliquus using residual filter paper and commercial HY zeolite (SiO₂/Al₂O₃ ratio = 60) as a heterogeneous catalyst. The biomasses were characterized by TGA/DTG and FTIR, where the microalga showed mass loss in three stages and an FTIR spectrum with characteristic bands of hydroxyl groups, amino groups, aliphatic chains, amides, and polysaccharides. The filter paper showed mass loss associated with dehydration and main degradation of cellulose, in addition to the typical FTIR profile of cellulosic materials (O–H, C–H, C=O bands). The HY catalyst was characterized by XRD, TGA/DTG, and FTIR, confirming the typical crystalline structure of Y zeolite (FAU), with characteristic peaks, thermal stability above 150 °C, and FTIR bands related to the aluminosilicate structure. Thermochemical tests were conducted in a batch reactor at 250 °C for 2 h in a N2 atmosphere with pure microalgae and with the addition of filter paper (25, 50, and 75%). The tests were performed without catalyst and comparatively with 10% HY zeolite. The liquid products obtained (bio-oils) were analyzed by TGA, FTIR, and GC/MS, where the processes without catalyst showed higher yields of the liquid fraction (up to 48.27% for 100% microalgae), while the addition of HY zeolite reduced this fraction and increased the gaseous phase (58.17% for 100M(HY)), indicating greater conversion of organic matter into gases. GC/MS analysis revealed a predominance of oxygenated compounds (82–100%) in all samples, with emphasis on carboxylic acids. HY zeolite promoted a moderate reduction of carboxylic acids only in the 100M(HY) sample (from 95% to 58%), with the appearance of esters. The content of nitrogenous compounds increased (from 6% to 21%) and the hydrocarbon fraction decreased (from 12% to 2%) in the catalyzed sample. In mixtures containing filter paper, the catalyst was visually inactive, maintaining oxygen levels close to 100%.
Síntese e caracterização do SAPO-11 visando à aplicação em reações de hidroisomerização
(Universidade Federal do Rio Grande do Norte, 2026-05-25) Fonseca, João Victor Lima da; GONDIM, Amanda Duarte; ARAÚJO, A. M. M; http://lattes.cnpq.br/4924374746045892; SILVA, Edjane F. B; http://lattes.cnpq.br/1736653643786951; http://lattes.cnpq.br/6738828245487480; http://lattes.cnpq.br/9982544911852245; ARAÚJO, Aruzza Mabel de Morais .; http://lattes.cnpq.br/4924374746045892; CAVALCANTI, Livia Nunes.; http://lattes.cnpq.br/4902766144157822; SILVA, Edjane Fabiula Buriti da.; http://lattes.cnpq.br/1736653643786951
The global energy landscape has undergone an intense transition in the pursuit of reducing greenhouse gas emissions, making biofuels promising alternatives for the partial replacement of fossil fuels. However, despite their environmental and energy potential, challenges related to production, economic viability, raw material availability, and technological limitations remain. In this context, catalysts play a fundamental role in the conversion of renewable hydrocarbons into fractions equivalent to those of fossil fuels. Thus, this work aimed at the synthesis and characterization of the catalytic material SAPO-11 for its application in isomerization reactions. The material was synthesized by hydrothermal crystallization using di-n-propylamine (DPA) as an organic structure driver and subsequently subjected to calcination in two stages, initially under a nitrogen flow and then under a synthetic air flow, promoting the controlled removal of the organic driver. After heat treatment, the material was characterized by different analytical techniques. X-ray diffraction results showed the preservation of the characteristic AEL crystal structure of SAPO-11, with maintenance of the main peaks at approximately 2θ = 8.1°, 9.5°, 13.2°, 15.7°, 20.3°, 21.2°, 22.1°, and 23.4°, indicating structural stability after calcination. The spectroscopic analyses confirmed the reduction of the bands associated with C–H bonds, while the TG/DTG thermal profiles demonstrated the disappearance of the thermal degradation events related to the organic structure-directing agent, evidencing the efficiency of the calcination process. The distinguishing feature of this work is the use of DPA as an organic directing agent, aiming to promote textural modifications and favor the generation of mesoporosity, minimizing diffusional limitations typical of microporous materials and potentially increasing catalytic efficiency in isomerization reactions.
Obtenção de SAF a partir da rota alcohol to jet com etanol e n-Butanol catalisado com Mo/HZSM-5
(Universidade Federal do Rio Grande do Norte, 2026-05-14) Zavaleta Villanueva, Sofia Anastacya Masçon; Gondim, Amanda Duarte; Araújo, Aruzza Mabel de Morais; Caldas, Amanda Menezes; Araújo, Aruzza Mabel de Morais; Cavalcanti, Lívia Nunes; Caldas, Amanda Menezes
VILLANUEVA, Sofia Anastacya Mascon Zavaleta. Production of SAF via Alcohol-to-Jet route using ethanol and n-butanol catalysed by Mo/HZSM-5. 2026. Monograph (Bachelor in Petroleum Chemistry) – Chemistry Institute, Federal University of Rio Grande do Norte, Natal, 2026. The objective of this study was to evaluate the potential of the Alcohol-to-Jet (ATJ) route for producing sustainable aviation fuels (SAF) from ethanol, n-butanol, and a mixture of the two (1:1), using a bifunctional Mo/HZSM-5 catalyst. The catalyst was synthesized from ZSM-5 zeolite, followed by ion exchange to obtain the acid form (HZSM-5) and subsequent impregnation with molybdenum (5% w/w). The materials were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), thermogravimetric analysis (TG/DTG), and scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS), confirming the preservation of the MFI crystalline structure, the incorporation of the metal without compromising the zeolite framework, and the thermal stability of the catalysts. The reactions were conducted in a batch reactor, and the liquid products obtained were analyzed by gas chromatography coupled with mass spectrometry (GC-MS), allowing for the identification and relative quantification of the formed compounds. n-Butanol stood out as the most promising feedstock, with a selectivity of 82.67% for C12 hydrocarbons — higher than that reported in the literature for unmodified HZSM-5. The 1:1 mixture exhibited 100% selectivity for C16, while ethanol produced a broader distribution, with hydrocarbons identified from C9 to C54. The results demonstrate the potential of the Mo/HZSM-5 catalyst for application in the ATJ route, with n-butanol as the most promising feedstock for SAF production in the aviation kerosene range.
Tratamento eletroquímico do efluente lixiviado com a cogeração de hidrogênio verde
(Universidade Federal do Rio Grande do Norte, 2025-12-15) Gondim, Ysla Karoline Ferreira; Martinez-Huitle, Carlos Alberto; Gondim, Amanda Duarte; Martinez-Huitle, Carlos Alberto; Costa, Leticia Gracyelle Alexandre; Araujo, Aruzza Mabel de Morais
Estudo da liquefação hidrotérmica da microalga scenedesmus sp com catalisadores Co/gamma-Al2O3 e Na2CO3
(Universidade Federal do Rio Grande do Norte, 2025-06-30) Silva, Anderson Bonifácio da; GONDIM, Amanda Duarte; ARAUJO, Aruzzza Mabel de Morais; FERNANDES, Rafael da Silva
Obtenção de biocombustíveis marítimos derivados de resíduos ovinos
(Universidade Federal do Rio Grande do Norte, 2025-09-30) Bezerra, Igor Cavalcante; GONDIM, Amanda Duarte; ARAÚJO, Aruzza Mabel de Morais.; https://orcid.org/0000-0002-4736-9847; http://lattes.cnpq.br/4924374746045892; https://orcid.org/0000-0001-6202-572X; http://lattes.cnpq.br/6738828245487480; https://orcid.org/0009-0007-3878-0873; http://lattes.cnpq.br/1566807170161283; Aruzza Mabel de Morais Araújo; https://orcid.org/0000-0002-4736-9847; http://lattes.cnpq.br/4924374746045892; Mayara Lopes Gundim de Macêdo; http://lattes.cnpq.br/0836545515974288
Fossil fuels remain the main sources of energy used in the maritime transport sector and are largely responsible for the emission of sulfur dioxide (SO₂), a component of greenhouse gases (GHG) that significantly contribute to global climate change. In response to this scenario, the International Maritime Organization (IMO) has established increasingly strict limits on sulfur content in marine fuels, encouraging the development of renewable and sustainable alternatives. In this context, this study aims to produce and characterize a biofuel obtained from the pyrolysis of sheep tallow, an agro-industrial residue with low cost and high energy potential. Initially, the biomass was subjected to thermogravimetric analyses (TGA/DTG) to evaluate its thermal behavior, identifying degradation ranges associated with the volatilization of fatty compounds. Physicochemical analyses, such as acid index, free fatty acid (FFA) content, and saponification index, were also performed, highlighting the lower FFA content of sheep tallow (1.9%) compared to bovine tallow (3.6%), which indicates better quality of the raw material for thermal conversion. The pyrolysis process, conducted under an inert atmosphere, yielded approximately 68% bio-oil, demonstrating good conversion efficiency. The obtained product, i.e., the bio-oil, was characterized by gas chromatography coupled with mass spectrometry (GC-MS), which allowed the identification of compounds mainly belonging to the hydrocarbon, ester, and fatty acid classes. Furthermore, physicochemical tests such as flash point, viscosity, and density indicated that the bio-oil exhibits properties that meet fuel and biofuel standards, especially when used in blends with marine diesel oil (DMA). These results demonstrate that sheep tallow is a promising raw material for the production of marine biofuels, offering a technically viable, economically attractive, and environmentally sustainable alternative. Therefore, the utilization of this residue contributes not only to the mitigation of SOx and GHG emissions but also to the valorization of agro-industrial by-products, aligning with the principles of the circular economy and international requirements for sustainable energy.
Uso dos sais de cálcio como estabilizadores de geopolímero para abandono de poços
(Universidade Federal do Rio Grande do Norte, 2025-11-19) Santos, Juliana Bernardo dos; Freitas, Júlio Cézar de Oliveira
Conversão térmica do óleo de milho de destilaria a partir de catalisadores mesoporosos
(Universidade Federal do Rio Grande do Norte, 2024-12-13) Brito, Ingrid Nayara de Medeiros; Gondim, Amanda Duarte; Araújo, Aruzza Mabel de Morais; http://lattes.cnpq.br/4924374746045892; http://lattes.cnpq.br/6738828245487480; https://orcid.org/0009-0005-9909-467X; https://lattes.cnpq.br/7439769233626414; Gondim, Amanda Duarte; http://lattes.cnpq.br/6738828245487480; Araújo, Aruzza Mabel de Morais; http://lattes.cnpq.br/4924374746045892; Castro, Karol de Sousa; http://lattes.cnpq.br/1801481370687639
Given the environmental impacts caused by fossil fuels, it is crucial to invest in the production of renewable energy and biofuels in order to contribute to a more sustainable future. When it comes to the use of biomass for conversion into biofuels, distillers corn oil (DCO) stands out as a promising energy source due to its excellent energy value. Recovered as a byproduct of ethanol production from corn, DCO contains fatty acids and esters, which can be converted into renewable hydrocarbons through several processes. Niobium (Nb) and alumina-based catalysts are considered efficient for the conversion of vegetable oils, offering high catalytic activity. This work focuses on the study of the thermal conversion of DCO, using the catalysts γ-Al2O3, Nb/γ-Al2O3 and NbOPO4. Previously, the physicochemical properties of DCO, such as acid value, saponification value, density at 15 °C, kinematic viscosity at 40 °C, Karl Fischer moisture content, and upper calorific value, were determined in order to confirm the characteristics of the raw material. Then, Thermogravimetric Analysis (TGA/DTG) of DCO was performed to evaluate its thermal decomposition. In addition, Gas Chromatography coupled to Mass Spectrometry (GC/MS) analysis was performed, identifying and quantifying the fatty acids that constitute DCO, present in the form of esters. To confirm the composition and crystalline structure of the catalysts, characterization techniques were performed, including X-ray Diffraction (XRD) and X-ray Fluorescence (XRF), mainly confirming the indication of materials with amorphous characteristics. The kinetic study of the different catalysts in contact with the oil was carried out at temperature rates of 10, 20, 30 and 40 °C/min in order to evaluate the catalytic activity of each one. A comparative evaluation of the OFW and KAS kinetic models was performed, which presented similarity in the linear adjustments of both. The methods employed revealed that the use of the catalysts resulted in a significant reduction in the energy required for the reactions to occur. It was possible to observe that the catalysts provide lower activation energies compared to the uncatalyzed process. However, the Nb catalysts demonstrated a considerably lower activation energy compared to γ-Al2O3, with an average difference of approximately 50 kJ.mol-1 between them, thus demonstrating better catalytic activity.
Produção de biocombustíveis a partir do óleo da polpa de macaúba: Estudo cinético
(Universidade Federal do Rio Grande do Norte, 2024-12-13) Silva, Sarah Rayanne de Lima; Gondim, Amanda Duarte; Araújo, Aruzza Mabel de Morais; http://lattes.cnpq.br/3299012094047628; Gondim, Amanda Duarte; Araújo, Aruzza Mabel de Morais; Queiroz, Gabriella Sousa de Melo
This reports the study of the thermal and catalytic conversion of macauba pulp oil for biofuel production. The study of the use of biomass, mainly of plant origin, has been gaining notoriety when compared to other sources, due to its characteristics and its wide ease of obtaining in our country. Macauba pulp oil (Acrocomia aculeata) presents excellent results because its composition is mostly composed of unsaturated fatty acids, giving the biofuel greater stability at low temperatures, preventing freezing and oxidation of the engine, improving its performance. In order to know the chemical composition of the oil, the physicochemical parameters analyzed were: acidity index (AI): 87.5 mg KOH/g, AGL: 39.8% A.O., kinematic viscosity evaluated at 40ºC: 42.9 mm²/s, density evaluated at 15ºC: 0.924 and saponification: 195.8 mg KOH. The NiO/γ-Al₂O₃ catalyst was synthesized by the incipient wet impregnation method and subsequently characterized by the analysis techniques of X-ray Diffraction (XRD), X-ray Fluorescence Spectrometry (XRF), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TGA). From the data obtained, it was possible to analyze the thermal and kinetic behavior of the oil in the presence of the catalysts. In order to understand the thermal conversion process of the oil, the kinetic study was carried out using the thermogravimetric analysis technique (TGA/DTA). The kinetic study was performed using the Kissinger-Akahira-Sunose (KAS) and Ozawa-Flynn-Wall (OFW) methods in the presence and absence of catalysts, and the activation energy (Ea) was determined with values between 83.37 and 167.11 kJ/mol for the pure oil, using the OFW model. A greater manifestation of the synergistic effect was observed, evidenced by the reduction in the apparent activation energy values, which varied between 62.92 and 126.89 kJ/mol for the OFW model, when the proportion of 10% of the impregnated metal to the catalytic support was used in comparison to the other catalysts. The most effective model for this study was the OFW.
Otimização da conversão térmica do óleo de Cártamo por meio de catalisadores microporosos
(Universidade Federal do Rio Grande do Norte, 2023-11-10) Souza, Maria Vitória Ferreira de; Gondim, Amanda Duarte; Araújo, Aruzza Mabel de Morais; https://lattes.cnpq.br/3028073987269163; Silva, Edjane Fabíula Buriti da
The excessive use of fossil fuels has led to serious environmental problems due to the emission of polluting gases into the atmosphere, contributing to the increase in global warming. Consequently, the pursuit of alternative options to minimize the impacts caused by fossil derivatives has gained significant attention in recent decades, driven by the global need to mitigate the damages caused by global warming. Based on this premise, this study explores the use of Safflower seed oil (Carthamus tinctorius L.) as a potential renewable source for obtaining biofuels. In order to better understand the pyrolytic behavior of safflower biomass, the work was divided into two stages: the first involved a literature review on biomass and its main compositional properties, as well as the ideal catalyst for the process. After the kinetic study conducted through thermogravimetric analysis (TGA/DTA), the pyrolysis conditions were defined, including the heating rate and residence time. The zeolite ZSM-5, chosen as the catalytic material for the study, was synthesized and characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA/DTA), scanning electron microscopy (SEM), and base adsorption acidity test (n-butylamine). The impregnation of Ni metal on the protonated HZSM-5 catalyst was carried out, followed by the repetition of characterization techniques, including X-ray fluorescence analysis (XRF). From this point, it was possible to analyze the thermal and kinetic behavior of the oil along with the use of catalysts. The characterization of the resulting bio-oil from these conventional and catalytic pyrolyses showed significant optimizations that, when analyzed by chromatography, revealed the enormous potential of safflower oil, with liquid product yields exceeding 70% in the traditional process and 90% when microporous materials were added to the process. Additionally, the inclusion of metallic oxide proved effective in deoxygenating the liquid products, enhancing the quality of the generated bio-oil. These promising results underscore the crucial role of these innovations in transforming oilseed biomass, opening new perspectives in biofuel production and emphasizing the potential impact on energy sustainability.
Descarbonização de combustíveis marítimos
(Universidade Federal do Rio Grande do Norte, 2023-11-09) Batista, Rebeca Rayane de Carvalho; Gondim, Amanda Duarte; Silva, Edjane Fabiula Buriti da; http://lattes.cnpq.br/6738828245487480; http://lattes.cnpq.br/7171711984740085; Hilário, Larissa Sobral
Estudo de correlação utilizando termogravimetria e destilação atmosferica no óleo diesel S10 comum
(Universidade Federal do Rio Grande do Norte, 2023-11-24) Lima, Andressa Conceição de Souza; Araújo, Antônio de Souza
This work is a case study in which, through the results of physical-chemical distillation tests using the ASTM D86 methodology, thermal analysis was carried out, to observe the profiles of the graphs obtained from the respective tests, and the development of a simulated methodology to obtain thermogravimetric analysis and atmospheric distillation test results. Initially, to optimize and define the methodology chosen for the thermal analysis of the work, a preliminary study is carried out on a TEST SAMPLE, the test is carried out using the open crucible and the crucible closed with a lid with a hole, in the heating bands using the respective heating rates 5°C, 10°C and 20°C and the same sample is subjected to the atmospheric distillation test, where the results obtained undergo a statistical analysis, and it was observed by Pearson's correlation coefficient that regardless of the heating rate, the correlation between the tests is valid, thus defining the use of a heating rate of 5°C/min with the use of a crucible closed with a lid with a hole in the TG, optimizing the study and defining a methodology. To continue the correlation study to obtain the simulated methodology, seven samples were subjected to thermal analysis at a heating rate of 5°C/min using a crucible with a perforated lid and atmospheric distillation. guarantee of the tests, and considering that the samples present results without interference, allowing the use of data by the analyzes in the application for determination through the use of the Excel tool to obtain equations that create a model of a simulated distillation curve and simulated thermal analysis. The results of the experimental simulated curve profiles showed that the studies carried out are valid and the variations in the graph profiles are in accordance with the data obtained for the development of the methodology.
Hidrocarbonetos avançados a partir da rota Alcohol-TO-JET com emprego da Zeólita ZSM-5
(Universidade Federal do Rio Grande do Norte, 2023-11-10) Sousa, Jessica Nicole Barros de; Gondim, Amanda Duarte; Araújo, Aruzza Mabel de Morais; http://lattes.cnpq.br/4924374746045892; http://lattes.cnpq.br/6738828245487480; http://lattes.cnpq.br/1680230399441499; Queiroz, Garbiella Sousa de Melo; http://lattes.cnpq.br/1891778571541208
This work reports the study of the production of renewable hydrocarbons for the production of sustainable aviation fuels from isobutanol alcohol as a source of biomass through the catalytic conversion steps of Alcohol-To-Jet technology (dehydration, oligomerization and hydrogenation) using zeolite ZSM-5 as catalyst. The H-ZSM-5 catalyst was synthesized hydrothermally in the absence of template and organic director. It was characterized by XRD, FTIR, XRF, TGA/DTG, MEV and acidity techniques by n-butylamine adsorption. The catalytic dehydration and oligomerization tests were carried out in a PVT furnace reactor under conditions of 280 °C and autogenous pressure, four percentages of catalyst (5%, 10%, 15% and 20%) were applied to the reaction medium with the objective to check the influence of this variable on the conversion. In parallel, the hydrogenation reaction was carried out independently under normal temperature and pressure conditions with the commercial Pd/C catalyst. Product analysis was carried out on a gas chromatograph with mass spectroscopy. The tests carried out showed that the potential of the dehydration and oligomerization steps directly depend on the catalyst concentration in the reaction medium. By increasing the concentration, dehydration becomes more efficient, with great selectivity of olefins in the C8-C16 range (aviation kerosene) above 50%. Considering that all assays showed a high alcohol conversion rate and yields greater than 50% for olefins in the BioQAV range. While the hydrogenation step obtained a high deoxygenation potential and 97.1% hydrogenation, generating paraffins with selectivity for the C8-C16 range, with the presence of branched aliphatic paraffins and cycloalkanes. Keywords: Isobutanol; Oligomerization; Alcohol-To-Jet; Biokerosene; H-ZSM-5
Hidrotratamento do óleo residual para produção de biocombustíveis
(Universidade Federal do Rio Grande do Norte, 2022-11-10) Brito, Luana Gabriela Costa; Godim, Amanda Duarte; Araujo, Aruzza Mabel de Morais; http://lattes.cnpq.br/7866007107748528; Fernandes, Rafael da Silva
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.
Obtenção de Biocarvão do fruto da Calotropis Procera com ênfase na adsorção de NI e V em água produzida
(Universidade Federal do Rio Grande do Norte, 2023-11-22) Paula, Icaro Silva de; Gondim, Amanda Duarte; Gondim, Amanda; Araújo, Aruzza; Anjos, Raoni
Desidratação da glicerina loira utilizando catalisadores ZnAl2O4 dispersos em zeólita beta
(Universidade Federal do Rio Grande do Norte, 2023-06-19) Nascimento Júnior, Marcos Antônio do; Braga, Tiago Pinheiro; Paulista, Adriana P. Figueiredo; http://lattes.cnpq.br/5559344770437847; http://lattes.cnpq.br/9170391410490804; https://lattes.cnpq.br/7551602710925635; Braga, Tiago Pinheiro; http://lattes.cnpq.br/9170391410490804; Araújo, Aruzza Mabel de Morais; http://lattes.cnpq.br/4924374746045892; Barbosa, Felipe Fernandes; http://lattes.cnpq.br/1536109877097445
Glycerol is the main by-product of biodiesel production. With its surplus on the market, its use in new conversion processes for the production of renewable sources for industry has become viable, enhancing the biodiesel production chain. The objective of this work is to evaluate the catalytic conversion process of blonde glycerin in the dehydration reaction of glycerol in gaseous phase with the use of acidic solids. Thus, catalysts were prepared by the wet impregnation method, with different contents of zinc aluminate dispersed in the beta zeolite. The catalysts were characterized by DRX and FTIR. XRD showed reflections characteristic of zeolite, but was inconclusive for the formation of aluminate due to the nanometric size and high dispersion of the particles, while FTIR showed characteristic bands of spinel and beta zeolite. The catalyst with the best result was 2Zn/BEA, which showed conversion of approximately 73%, with major selectivity for allyl alcohol with approximately 37% in 600 min of reaction. This result is related to the presence of acidic and basic sites in the catalyst, which are related to the formation of the products obtained, which detailed the mechanism for the formation of the products obtained, mainly of allyl alcohol by hydrogen transfer. Subsequently, the evaluation of regeneration and reuse of the catalyst was carried out, with four cycles, which showed excellent conversion and stability results, showing approximately 81.47% of conversion at the end of all reuses. Finally, the catalyst was subjected to a new XRD and TG analysis, confirming its structural stability and resistance to coke deposits.
Síntese e Caracterização de SBA-15: Suporte para catalisadores óxidos de Cu, Zn, Zr para hidrogenação de CO2
(Universidade Federal do Rio Grande do Norte, 2023-06-16) Jales, Mateus Madson do Nascimento; Pergher, Sibele Berenice Castellã; Mello, Mariele Iara Soares de; http://lattes.cnpq.br/8225162650698181; http://lattes.cnpq.br/5249001430287414; https://orcid.org/0000-0001-9736-5601; https://lattes.cnpq.br/5931340652108058; Pergher, Sibele Berenice Castellã; http://lattes.cnpq.br/5249001430287414; Mello, Mariele Iara Soares de; https://orcid.org/0000-0002-5979-2474; http://lattes.cnpq.br/8225162650698181; Araújo, Aruzza Mabel de Morais; http://lattes.cnpq.br/4924374746045892; Bieseki, Lindiane; https://orcid.org/0000-0002-0088-0963; http://lattes.cnpq.br/4894556873583410
The use of oil and its derivatives increases carbon emissions and the concentration of atmospheric CO2, the main greenhouse gas (GHG), which has reached more than 400 ppm in recent years, directly impacting climate change and rising temperatures. from the planet. CO2 is an inert and highly selective molecule, which configures the need for catalytic species with such selectivity and efficiency for its conversion. Therefore, the objective of this work is the development of mesostructured supports with specific properties, suitable for the incorporation of metals and subsequent application to the catalytic hydrogenation of CO2 to methanol. Supports of the SBA-15 type were synthesized with hexagonal type morphology (fibers), and platelet and medium pore type morphologies with the addition of decane and dodecane, respectively. The observed diffractometers showed characteristic peaks that characterize the formation of the material of the SBA-15 type, in addition, the formation of the proposed morphologies was observed by micrographs, except for the platelet type, due to the disruption of the formed particles. The addition of alkanes caused displacement of the main peaks, increasing the mesoporous parameters and the interplanar distance of the materials, as well as modifying the average size of the formed particles. In addition, it caused a significant reduction in specific surface areas and total pore volume, while micropore volume, pore diameter and wall thickness increased.
Desenvolvimento de um nanossensor de prata para detecção e quantificação de íons incrustantes na indústria do petróleo
(Universidade Federal do Rio Grande do Norte, 2023-06-06) Caldas, Amanda Menezes; Balaban, Rosangela de Carvalho; Fernandes, Rafael da Silva; 0000-0002-4117-7035; http://lattes.cnpq.br/0271263232319722; 0000-0002-7587-6010; http://lattes.cnpq.br/7711521318854102; 0009-0001-3178-5619; http://lattes.cnpq.br/3615366618228937; Neto, Alcides de Oliveira Wanderley; 0000-0002-0991-8526; http://lattes.cnpq.br/4789528535524269
In this work, a simple silver nanosensor (AgNPs-PYRO) was developed by the reduction method with sodium citrate and sodium borohydride at low temperatures. The nanosensor showed satisfactory performance in the detection of barium ions (Ba+2), strontium (Sr+2), magnesium (Mg+2), calcium (Ca+2), and iron (Fe+3), scales from the oil industry. The analysis carried out through UV-Vis spectroscopy allowed identifying the species at concentrations between 0.5 and 10 ppm. In addition, the obtained colors also made it possible to distinguish the bivalent species (Ba+2, Sr+2, Mg+2, and Ca+2) and iron III, trivalent. The decrease in the plasmon band at 400 nm after the addition of the metallic sample, directly related to the stability of the nanosensor, indicated the destabilization and aggregation of AgNPs. The morphology was analyzed by FE-SEM, where silver showed a size of approximately 20 nm and uniform distribution. After adding barium, it was possible to observe relatively empty spaces and the aggregation of nanoparticles, which is the detection mechanism of the proposed nanosensor. The Zeta potential values obtained for the samples AgNPs, AgNPs-PYRO and AgNPs-PYRO-Metal were -25.0, -52.2, and -43.2, confirming that the sensor is based on the aggregation process since the decrease in charge is a sign of less stability. The nanosensor proved to be sensitive to metals, where the inserted samples resulted in colors of different intensities, proportional to the concentrations. The obtained results prove that the nanosensor is efficient for qualitative and quantitative analysis of these species involved in the scaling process, in an easy and simple analysis, and can be used as an alternative method for this application.
Avaliação cinética do bagaço da Cana Energia para a produção de biocombustíveis
(Universidade Federal do Rio Grande do Norte, 2022-12-20) Silva, Dhiovana Furtado da; Gondim, Amanda Duarte; https://orcid.org/0000-0001-6202-572X; http://lattes.cnpq.br/6738828245487480; 0000-0003-4071-8685; http://lattes.cnpq.br/8206077414641615; Araújo, Aruzza Mabel de Morais; https://orcid.org/0000-0002-4736-9847; http://lattes.cnpq.br/4924374746045892; Castro, Karoline de Sousa; https://orcid.org/0000-0002-8502-345X; http://lattes.cnpq.br/1801481370687639
The excessive consumption of fossil energy has been the subject of worldwide discussions due to the environmental problems generated by its use. With this, studies have been developed considering a new source of energy, biomass, a renewable energy source and with less negative impacts on the environment. Biomass from Cana Energia has characteristics modified from conventional sugarcane to be more productive in the manufacture of biofuel and generation of renewable energy. acetylation, to make its fiber more accessible in the thermal and thermocatalytic pyrolysis process, and consequently produce biofuels with high added value. For this purpose, the objective of this work is to evaluate the behavior of catalysts impregnated with cobalt in the thermochemical conversion of Cana Energia. The obtained catalytic materials were characterized by X-ray fluorescence spectroscopy (FRX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). It can be observed through the FRX, DRX and FTIR techniques that there was impregnation of the oxide and that the material did not present changes in its structure after the incorporation of Cobalt. As lignocellulosic biomass has a highly stable vegetal crystalline structure, Cana Energia was acetylated and analyzed by thermogravimetry, in which the behavior shown proves the replacement of hydroxyl-OH groups by acetyl-COCH3 groups due to the decrease in degradation temperature intervals. The biomass with and without the presence of catalysts was analyzed by thermogravimetry in order to evaluate the kinetic parameters by the Ozawa-Flynn-Wall (OFW) and KissingerAkahira-Sunose (KAS) models. The results found that the model that best fits is the KAS, because the R² values in this model are closer to the expected. Based on the activation energy (Ea) results, it is inferred that the biomass in the presence of the Al2O3 catalyst presented the lowest values of activation energy (Ea) in relation to the isolated biomass.
Nanopartículas poliméricas em sistema de pastas de cimento para controle de filtrado em poços petrolíferos
(Universidade Federal do Rio Grande do Norte, 2023-06-07) Viana, Antonio Leonardo; Freitas, Julio Cezar de Oliveira; https://orcid.org/0000-0003-1324-9705; http://lattes.cnpq.br/2357217530716519; https://orcid.org/0000-0002-8251-0797; http://lattes.cnpq.br/7024709372377961; Santiago, Rodrigo César; http://lattes.cnpq.br/6823966481089536; Batista, Willame Gomes da Silva; https://orcid.org/0000-0003-1293-7688; http://lattes.cnpq.br/0592299905652957
Cementation is one of the most important stages during the oil well construction process and its function is to ensure the fixation and protection of the metallic casing installed in the well, in addition to preventing the migration of fluids and gases from the rock formation. However, during the process of pumping the cement slurry into the annular space, a pressure difference occurs which results in the aqueous phase of the slurry filtering through the rock formation, leaving only the solids behind. The objective of this work is the application of polymeric polystyrene nanoparticles as a chemical additive for the control of filtrate in cement pastes for application in oil wells. The tests were carried out simulating a vertical well with 1700m of depth and geothermal gradient of 1.50°F/100 feet. Pastes with a specific mass of 15.8 lb/gal were formulated using class G Portland cement with nanolatex concentrations ranging from 0 to 2.0 gpc. API filtration, rheology, thickening time and stability tests were performed. The obtained results show that nanolatex is a highly efficient additive in the control of cement paste filtrate. Another significant result was the reduction in setting time, which can be attributed to the greater stability provided by the nanolatex to the cementitious system. Furthermore, it was possible to conclude that with the increase in nanolatex concentrations there was an increase in the values of the rheological parameters.

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