|
Disertaciones |
|
1
|
-
MARCOS LAPA BRITO
-
COMPARISON BETWEEN ETHANOL AUTOTHERMAL REFORMING AND METHANE STEAM REFORMING USING MULTIVARIATE ANALYSIS
-
Líder : GEORGE SIMONELLI
-
MIEMBROS DE LA BANCA :
-
GEORGE SIMONELLI
-
JOSE MARIO FERREIRA JUNIOR
-
LUIZ CARLOS LOBATO DOS SANTOS
-
JOSE BAPTISTA DE OLIVEIRA JUNIOR
-
Data: 29-ene-2020
-
-
Resumen Espectáculo
-
Autothermal reform of ethanol is an alternative route to steam reforming of methane to produce hydrogen, using renewable raw material and being able to achieve self-sufficiency in its main reactor. This work carried out simulations using the Aspen HYSYS dynamic process simulation software for both reforms, from variations in temperature, steam / raw material ratio and oxygen / ethanol ratio in order to compare them in terms of hydrogen production and the energy consumption of its main reactors. For both reforms, we found significant empirical statistical mathematical models for hydrogen production and energy consumption. In the autothermal reform of ethanol there was a quadratic effect of temperature and a negative interaction between it and the oxygen / ethanol ratio for hydrogen production and energy consumption in its reformer. The maximum production of the methane reform was 4.00 molH2 / molCH4, under process conditions (pressure: 20 bar; temperature: 1000 ºC; steam / methane: 5.00 mol / mol), with an efficiency of 90% and energy consumption in the reformer of 358.51 kJ / molmet. Under pressure conditions: 20 bar; temperature: 1000 ° C; steam / methane: 5.00 mol / mol; oxygen / ethanol 0.18 mol / mol, the autothermal reform of ethanol showed an efficiency of 86.33% and produced 5.41 molH2 / molC2H5OH. These results represent a 35.25% increase in relation to the methane reform with the same energy expenditure in the main reactor (358.51 kJ / molC2H5OH). For the autothermal reform of ethanol, changing the oxygen / ethanol ratio to 0.90 mol / mol does not cause external energy consumption by the main reactor as it produces 5.00% higher than that obtained by the plant with 4.20 molH2 / molC2H5OH methane . These results allow us to affirm that the autothermal reform of ethanol is competitive, compared to the steam reform of methane, as it produced a greater amount of hydrogen with less energy consumption.
|
|
2
|
-
CÉLIA KARINA MAIA CARDOSO
-
INETIC AND EQUILIBRIUM STUDY OF OIL ADSORPTION USING PRE-TREATED COCONUT FIBERS
-
Líder : ANA KATERINE DE CARVALHO LIMA LOBATO
-
MIEMBROS DE LA BANCA :
-
ANA KATERINE DE CARVALHO LIMA LOBATO
-
DENILSON DE JESUS ASSIS
-
ICARO THIAGO ANDRADE MOREIRA
-
OLIVIA MARIA CORDEIRO DE OLIVEIRA
-
Data: 30-ene-2020
-
-
Resumen Espectáculo
-
Despite the variety of renewable energy sources today, fossil sources are still the main sources in the world. The growth in oil production that favors the stability of the economy through positive impacts on the social, scientific and technological sector is the same that presents serious risks to the environment and consequently to human health. The oil spill catastrophe that recently occurred on the Brazilian coast serves as an alert for the development of research that contemplates the prevention of environmental accidents, mainly the development of biotechnological processes and products for cleaning marine environments. Thus, the use of natural sorbents to remedy impacted areas has been a promising alternative, since they are biodegradable and available in nature. Therefore, this work aims to compare the use of residual coconut fibers (Cocos nucifera L.) in natura and pretreated with Practical Ionic Liquid (LIP) [2-HEA] [Ac] and by mercerization / acetylation for remediation petroleum spilled in the marine environment, using a hydrodynamic simulation on a laboratory scale. The chemical pretreatments (traditional methods: mercerization / acetylation and innovative: with LIP), the characterization of the fibers (in natura and treated) were carried out using the Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectroscopy (FITR) , and in the kinetics and sorption balance tests using Campos Basin oil and artificial saline water. It was found that the morphological structure of the fibers treated with LIP had a greater amount of pores and that the mercerized / acetylated fibers had a rougher surface when compared to fibers in natura. As for the sorption kinetics, it was possible to observe that time does not influence sorption, requiring a short contact time between the adsorbent and the adsorbent for biosorption to occur. The kinetic model that best fitted the experimental data was the pseudo-second order, indicating that the limiting step in the process is chemorsorption. In addition, the biosorbents entered into a sorption equilibrium from 6.0 mL of oil spilled in 94.0 mL of saline water. The experimental data showed a greater correlation with the data from the Sips model for all fibers studied, indicating that the adsorption is reduced to the Freundlich isotherm (multilayer) in low oil concentrations and to Langmuir (monolayer) in high concentrations. Finally, fibers treated with LIP adsorbed 25.5% (5.37 g / g) more than fibers in natura (4.00 g / g) and 20.5% more than mercerized / acetylated fibers (4.27 g / g). Based on these results, it can be said that treated fibers have a greater capacity to adsorb oil than fibers in natura, and fibers treated with LIP have greater sorption capacity compared to conventionally treated fibers, which can be used in oil spills.
|
|
3
|
-
ALEXANDRE SANTARÉM ZIMMERMANN
-
Prediction of tThermophysical properties of binary liquid mixtures ammonium based ionic liquids and water using
feedforward and cascade forward neural networks
-
Líder : SILVANA MATTEDI E SILVA
-
MIEMBROS DE LA BANCA :
-
MÁRCIO LUIS LYRA PAREDES
-
REGINA FERREIRA VIANNA
-
SILVANA MATTEDI E SILVA
-
Data: 12-feb-2020
-
-
Resumen Espectáculo
-
The increase of the application of the substances known as ionic liquids and consequent need to obtain their properties and the properties of their mixtures in a wide range of temperature and composition make the development of new models mandatory, so the process of data obtaining gets cheaper and faster. Neural networks are a method widely used in several areas of science and engineering, including properties prediction. Hence, the present work focused on studying the prediction of density, speed of sound and viscosity of binary mixtures of ammonium-based ionic liquids and water and how network configuration changes influence the prediction performance. The network training was carried out using literature data. Temperature, ionic liquid mass fraction and the amount of each structural group (used to characterize the ionic liquid) were used as input variables. The obtained results showed the neural networks as an important asset for modeling the thermophysical properties of ionic liquids and their mixtures, achieving average absolute relative deviations of 0.0107%, 0.1%, 0.2% during the prediction of density, speed of sound and viscosity, respectively. When compared to neural models available in the literature, the neural network of this work presented a better performance when predicting density and viscosity and an almost equivalent performance when predicting speed of sound. The maximum errors were also considered suitable and relevant trends or systematic errors were not observed during the predictions.
|
|
4
|
-
JAVAN GRISENTE DOS REIS DA COSTA
-
EVALUATION OF GLYCEROL AS AN ADDITIVE IN THE ELECTRODEPOSITION OF Ni AND Ni-Mo
-
Líder : CARLOS ALBERTO CALDAS DE SOUSA
-
MIEMBROS DE LA BANCA :
-
CARLOS ALBERTO CALDAS DE SOUSA
-
CLAUDIA LISIANE FANESE DA ROCHA DE RESENDE
-
GEORGE SIMONELLI
-
VANESSA SILVEIRA SILVA
-
Data: 28-feb-2020
-
-
Resumen Espectáculo
-
The use of organic compounds as an additive to improve corrosion protection of carbon steel has been gaining ground, especially in electroplating. In order to improve corrosion protection using Ni and Ni-Mo deposits, the present work describes an investigation of the addition of glycerol fractions (0.0; 0.07; 0.27; 0.82 mol.L-1) on AISI 1020 carbon steel in acidic (0.5 mol.L-1 NaCl) and basic (0.5 mol.L-1 NaOH) medium at times of 24, 48 and 72 hours. The addition of glycerol has a positive effect on the deposition efficiency of Ni and Ni-0.3Mo, as well as reducing the energy consumption spent in the process, or which is interesting in industrial application. In corrosion analysis, the corrosion rate in NaCl and NaOH medium is observed, the reduction in corrosion rate occurs as the amount of glycerol increases for Ni and Ni-Mo deposition. Confirmation of the study is corroborated by the polarization curves, where it is possible to observe larger polarizations to the values of 0.82 mol.L-1, and by electrochemical impedance spectroscopy. Despite the reduction in microhardness provided by glycerol, the expressive results of corrosion resistance suggest non-friction environments, this application is valid. The morphology of the deposits was loaded with XRD, roughness and SEM techniques, which is noted as an increase in roughness for Ni bath and a decrease for Ni-0.3Mo. This difference can be expressed by SEM, where the Ni bath apparently overlaps the deposit predominantly by the structures (111) and (200) and the reduction for the Ni-0.3Mo bath is observed by the reduction of vacations that occur. SEM presented as glycerol is increased, mainly due to Mo structure (313). It is noteworthy that although glycerol influences different shapes in the baths, a corrosion resistance is improved, regardless of the corrosion in the medium.
|
|
5
|
-
MANUELA LISBÔA DE OLIVEIRA
-
2-METHYLTHIOPHENE REACTIONS ON MODIFIED KSF CLAYS
-
Líder : LUIZ ANTONIO MAGALHAES PONTES
-
MIEMBROS DE LA BANCA :
-
LUIZ ANTONIO MAGALHAES PONTES
-
MARIA LUIZA ANDRADE DA SILVA
-
RONALDO COSTA SANTOS
-
SIBELE BERENICE CASTELLÃ PERGHER
-
Data: 27-abr-2020
Ata de defesa assinada:
-
-
Resumen Espectáculo
-
The content of sulfur compounds present in fuels, used in internal combustion automotive engines, has been increasingly controlled due to stricter environmental regulations in force in several countries. The reduction of thiophenic compounds, in particular, presents a high degree of complexity due to the electronic stability of the aromatic ring. Thus, there is a search for cleaner processes and materials, with high selectivity, economic viability and that allow the reduction of thiocompounds with formation of H2S or through the opening of the ring, providing the formation of open chain products, which are more easily eliminated. In this context, this study evaluated the transformations of 2-methylthiophene, as a model compound in a n-hexane stream, using pillared activated clays and incorporated with zinc, in order to evaluate the opening of the thiophene ring and the formation of H2S. The reactions took place at a temperature of 450 °C, under atmospheric pressure, with a spatial speed of 0.83 s-1. The clays were modified by incorporating alumina pillars and zinc impregnation. Textural, structural and physical-chemical modifications were analyzed by XRD, N2 adsorption and desorption, XRF, SEM, TG, DRIFTs – C5H5N, DPT - NH3 and TPO. The catalysts were evaluated in a laboratory unit dedicated exclusively to studies of transformation of sulfur molecules. The acidity of the catalyst and the secondary reactions of hydrogen transfer were evaluated and related to the formation of the products. Catalysts with a higher ratio of Brønsted/Lewis acid sites promoted hydrogen transfer reactions, favoring the production of H2S, while those with a greater amount of Lewis acid sites favored the formation of mercaptan. Pillared clays led to preferential formation of 2-propanethiol, while non-pillared clays formed more H2S. The most selective catalyst for the formation of 2-propanethiol was Zn/KSF-PILC (67%) while KSF and Zn/KSF, formed more H2S, (94% and 88%, respectively).
|
|
6
|
-
DAVI NASCIMENTO FERREIRA
-
Analysis of paraffin deposition using a semi-empirical model and the response surface methodology
-
Líder : LUIZ CARLOS LOBATO DOS SANTOS
-
MIEMBROS DE LA BANCA :
-
GEORGE SIMONELLI
-
JOAO PAULO LOBO DOS SANTOS
-
LUIZ CARLOS LOBATO DOS SANTOS
-
LUIZ MARIO NELSON DE GOIS
-
Data: 06-may-2020
-
-
Resumen Espectáculo
-
Wax deposition in pipelines is a recurring problem in the oil industry which has gained even more relevance with the growth of offshore production in deep environments. Therefore, several studies have been conducted aiming at a better understanding of such phenomenon, as well as to provide estimates regarding the precipitate layer. Information such as this can be useful to support the decision-making process related to pipelines and production units. However, the study of wax deposition is strongly dependent on the performance of experiments, which are often costly and may make the analysis unfeasible. As an alternative to test-dependent methodologies, we have developed a model for estimating the thickness of the deposited wax layer. By combining a solubility equation with a one-dimensional and steady-state thermal model, we were able to obtain thickness values with deviations below 3% for a cylindrical shape. The results for a square duct showed that the model is not able to represent the gradual growth of deposits. The obtained data enabled the development of a significant statistical model, in which the temperature was the most determinant variable in the process, regarding the conditions under analysis.
|
|
7
|
-
GABRIELLE DAS VIRGENS FRAGA
-
PERSPECTIVES AND CHALLENGES OF ITACONIC ACID PRODUCTION FROM BIOMASS
-
Líder : LEONARDO SENA GOMES TEIXEIRA
-
MIEMBROS DE LA BANCA :
-
LEONARDO SENA GOMES TEIXEIRA
-
LUIZ ANTONIO MAGALHAES PONTES
-
CAIO LUIS SANTOS SILVA
-
LEILA MARIA AGUILERA CAMPOS
-
Data: 07-may-2020
-
-
Resumen Espectáculo
-
The concern about the environmental scenario and the climate changes that the planet has been suffering becomes constant in the search for the development of cleaner industrial chain products obtained from renewable sources. From this perspective, the United States Department of Energy (US DOE) conducted a mapping, following economic and technological evaluations, of molecules called platforms, twelve of which have a huge competitive nature and can be produced from sugar from biomass. Itaconic acid (IA) is a very promising platform molecule due to the possibility of obtaining products such as methyl methacrylate and synthetic latex, with the prospect that its global market will grow at an average annual rate of 4.3% (CAGR) from 2019 to 2025, exceeding $125 million in sales. The main technological route used to obtain IA is fermentation using variations of the fungus Aspergillus. In this dissertation, a survey of the main technologies involving the process of biosynthesis of IA from biomass was carried out, based on the evaluation of published scientific articles and patents, establishing a critical analysis regarding these technologies, as well as their production prospects for the coming years. The main advances are related to genetic engineering since Aspergillus terreus is more tolerant of the conditions used in the synthesis and optimization of the process. The main substrate used is glucose (52%), followed by glycerol (25%). Among the results presented in the research, the best productivity occurred with U. maydis, with 220 g/L of IA, with a yield of 0.33 g/g, using glucose as a carbon source. Combined with the choice of the best microorganism, the fundamental factors that must be observed to increase the productivity of IA, consist of the morphology of the employed fungus, pH and mean components present during the fermentation stage, the determination of the conditions of this step is directly linked to the costs involved during the process. In short, even though IA is a platform molecule with great economic potential, it is still necessary to continue optimizing its biotechnological process so that production can be vantageous.
|
|
8
|
-
MONIQUE EVA DE JESUS TRINDADE
-
Protic ionic liquid ([DETA] [Hx]) as a co-solvent in the production of biodiesel
-
Líder : LUIZ CARLOS LOBATO DOS SANTOS
-
MIEMBROS DE LA BANCA :
-
CAETANO MORAES
-
GEORGE SIMONELLI
-
LUIZ CARLOS LOBATO DOS SANTOS
-
SILVANA MATTEDI E SILVA
-
Data: 08-may-2020
-
-
Resumen Espectáculo
-
Ionic liquids (ILs) have been outstanding in many industrial applications due to their interesting properties, such as its designability, good solubility in organic and inorganic compounds, moderate surface tension, low vapor pressure, thermal and chemical stability. In biodiesel production, aprotic ionic liquids (AILs) are normally used as catalysts. For this purpose, considerable amounts of this compound must be used in the reaction, as well as higher temperatures and methanol:oil molar ratio are required, increasing the costs of production. Protic ionic liquids (PILs) when compared to AILs are less expensive, less toxic and have simpler synthesis. Some of these compounds can be synthesized with the presence of hydrophilic and hydrophobic groups in their structure, presenting surfactant characteristics, therefore, promoting the interfacial tension reduction. Exploring its surfactant activity, low concentrations can be applied in the transesterification reaction of vegetable oils with the advantage of improving the immiscible phases (alcohol and oil) contact, increasing the reaction rate and the biodiesel yield. In the literature, few scientific studies have investigated the application of PILs as co-solvent in the alkaline transesterification of oils or fats. Generally, ILs are used in enzymatic catalysis processes in order to preserve biocatalysts and, for this purpose, AILs are preferred. Thus, this study evaluates the use of the protic ionic liquid diethylenetriammonium hexanoate ([DETA][Hx]) as co-solvent in the homogeneous alkaline reaction of soybean oil and methanol for biodiesel production. A factorial design of 2 independent variables was performed to evaluate the effects generated on the biodiesel yield by the variation of the concentration of [DETA][Hx] and the reaction time. The statistical analysis showed that the use of small amounts of co-solvent is enough to increase the yield in 5.10%, reaching 97.06% with only 3% w/w of [DETA][Hx] in the reaction medium in 30 minutes. In the second stage, cascade experiments were carried out to obtain the optimum point of biodiesel production, whose mass yield was 99.53%. The optimal reaction conditions were achieved under 2.0% (w/w) of PIL [DETA][Hx], methanol:oil molar ratio of 7:1, 1.0% KOH as catalyst, 30 °C and 10 min reaction. The results demonstrate that the application of PIL [DETA][Hx] as a co-solvent was promising, as it promotes the reduction of the interfacial tension between the phases, improves the reagents solubility in milder reaction conditions and consequently increases the mass yield. The biodiesel produced at the optimum point was characterized to verify compliance with the specifications of ANP Resolution No. 45/2014, ASTM D6751 and EN 14214.
|
|
9
|
-
Rafaela Maria de Sá Telles Martins
-
DESIGN OF FIRE PROTECTION AND FIRE FIGHTING SYSTEMS IN LPG STORAGE PARKS:
A COMPARATIVE STUDY BETWEEN BRAZILIAN AND INTERNATIONAL STANDARDS
-
Líder : REGINA FERREIRA VIANNA
-
MIEMBROS DE LA BANCA :
-
REGINA FERREIRA VIANNA
-
GEORGE SIMONELLI
-
HERBERT PEREIRA DE OLIVEIRA
-
Data: 11-ago-2020
-
-
Resumen Espectáculo
-
Liquefied petroleum gas (LPG) is one of the products of petroleum refining and natural gas processing units; in refineries and distribution terminals it is usually stored in spherical or cylindrical storage vessels, since a large amount of this product is produced or handled in these facilities. Due to the LGP high destructive risk, such as occurred at a processing plant in the Gulf of Mexico and Duque de Caxias Refinery, national and international standards and codes has been created for the design of fire fighting systems in LGP industrial facilities. This paper presents a comparative study of design standards for fire protection and fire fighting systems in LPG storage parks, with a view to achieving a safer and more economical design. In particular, the fire protection and fire fighting methods and cooling water rates and flow rates proposed for three different cases are compared: (1) Technical Instruction No. 28 (2017) of the Bahia Military Fire Department, which is similar to Instruction of other Brazilian Military Fire Brigades; (2) PETROBRAS Standard N-1203 (2013); and (3) International Petroleum Institute API-25010 (2011) and API-2510A (2015) International Standards. As a case study, a park of LPG storage spheres was analyzed, where the spheres to be cooled and the required water flows in Cases 1 and 2 were determined, using the data prescribed by the standards. For Case 3, the ALOHA simulator was used to calculate the radius of action of the thermal radiation rate, and then select the spheres to be cooled. In particular, it was found that Case 3 was the one with a cost, approximately 36% lower than the others, in relation to pipes and equipment. It was also found that Brazilian standards are more prescriptive and obsolete in the face of advances in Fire Engineering, which may render the project inadequate, as they do not take into consideration the environmental risks and conditions of the analyzed facility. International standards, however, proved appropriate by proposing site analysis using realistic fire exposure scenarios to determine equipment to be protected and water flows and rates. As an additional result, a systematic methodology for designing fire protection and fire fighting systems was proposed, bringing together several procedures described in the literature. In general, this work has potential use for application in other types of industrial facilities dealing with the storage of flammable substances.
|
|
10
|
-
TIARI RAMOS REZENDE
-
Study of the use of nanofluids in a heat exchanger plates through computational fluid dynamics
-
Líder : SAMUEL LUPORINI
-
MIEMBROS DE LA BANCA :
-
SAMUEL LUPORINI
-
LUIZ MARIO NELSON DE GOIS
-
REGINA FERREIRA VIANNA
-
ELILTON RODRIGUES EDWARDS
-
Data: 14-ago-2020
-
-
Resumen Espectáculo
-
This work proposes to obtain information on the use of nanofluids as the coolant in the plate heat exchanger, using CFD (Computational Fluid Dynamics), since there is a need for studies on the performance of these systems. ANSYS Fluent CFD software was used, whose simulation strategy is finite volume methods. With this tool, 3D simulation of a plate heat exchanger operating with Al2O3 nanofluid was made in selected 2%, 3%, and 4% in the volume of solution as a coolant and pure water as hot fluid. An analysis was also carried out for different coolant fluxes, ranging from 2 lpm to 5 lpm. Additionally, an analysis with the plate corrugation angle at 30º and 60º were run. Validation was made obtaining a good approximation, about 90% accuracy, in relation to the heat transfer coefficient experimentally in previous studies of Pandey e Nema (2012), which was the use of the values for construction of geometry and operation test. The use of nanofluids at higher concentrations, up to 4%, that was analyzed in the heat exchanger, shows a good influence on the thermal unemployment. The angles of 30º and 60º present between the plates also promote better heat exchanger performance when compared to geometry without angulation. The flow variations of the nanofluid must take into account the pressure drop adequate for the process in which the heat exchanger is applied since the increase in flow gives a significant increase in pressure drop.
|
|
11
|
-
TARCISIO DE OLIVEIRA PEREIRA
-
Particle property of the sisal residue during the pyrolysis reaction in a fluidized bed reactor.
-
Líder : CARLOS AUGUSTO DE MORAES PIRES
-
MIEMBROS DE LA BANCA :
-
CARLOS AUGUSTO DE MORAES PIRES
-
SAMUEL LUPORINI
-
CRISTIANO HORA DE OLIVEIRA FONTES
-
Data: 28-ago-2020
-
-
Resumen Espectáculo
-
This study presents a mathematical model in a transient regime capable of predicting the production of coal in a rapid pyrolysis process, from a fluidized bed reactor. The model was developed from the thermal decomposition of a sisal particle and its solution depended on data not reported in the literature. The convective coefficient of the reaction medium was found from experimental data from the pilot unit, involving heats given and dissipated by the reaction system. The surface temperature of the particle was measured in a new bench test, in which some particles were transformed by pyrolysis at a fixed reaction temperature. The surface temperature of a set of particles was measured at each reaction time, as well as their diameters and masses. The specific mass of the particle was measured with the aid of gas pycnometry, using the particles obtained in the surface temperature measurement experiment. From the results of the particle specific diameters and mass, it was possible to determine their calorific capacities. The system of equations obtained was solved in MATLAB environment, obtaining profiles of surface temperature and particle mass throughout the reaction. The data required to calculate the theoretical coal mass of a pilot pyrolysis unit were the particle diameter, obtained from the model simulation, and the resulting particle speeds in the reactor, obtained from a balance of forces in a particle. The calculated particle residence time was 35 s, and the calculated coal mass had a 6.38% discrepancy in relation to data collected in the pilot production unit.
|
|
12
|
-
FELIPE MENEZES DE SOUZA
-
EVALUATION OF MIXING OF XANTHAN GUM AND MONTMORILLONITE NANOCLAY FOR THE DEVELOPMENT OF DRILLING NANOFLUID
-
Líder : SAMUEL LUPORINI
-
MIEMBROS DE LA BANCA :
-
DENILSON DE JESUS ASSIS
-
GLEICE VALERIA PACHECO GOMES
-
ISABEL CRISTINA RIGOLI
-
SAMUEL LUPORINI
-
Data: 25-sep-2020
-
-
Resumen Espectáculo
-
With the estimated increase in oil demand for the coming decades, the need for exploration of unconventional areas intensifies, and associated with them, given the high exploration costs, the need to improve available technologies. In this sense, in the last decade, the application of nanoparticles for the improvement of drilling fluids has intensified. In this scenario, montmorillonite nanoclays and xanthan gums were little explored for the development of nanofluids. For this work, the influence of the hydrophobic and hydrophilic montmorillonite nanoclays on the rheological parameters of xanthan solution containg sodium and calcium chlorides was verified. For that, the experimental analysis for each clay was divided. For hydrophobic clay, nanoclay was first characterized with XRF, XRD and TGA; then, a complete factorial design 24 was adopted, varying the concentrations of nanoclay, xanthan, sodium and calcium chlorides; thirdly, a Doehlert Matrix of the 7x5x3 type was adopted, varying the concentrations of nanoclay, xanthan and temperature, with the concentrations of the constant salts; fourth, the dispersion of the mixtures was evaluated with differing rheological parameters and respective Conductivity and Zeta Potentials. For hydrophilic clay, the clay was also primarily characterized by DRX, FRX and TGA. Then, under one-dimensional experimental planning in triplicate, it was evaluated: the influence of the variation in the concentration of nanoclay on the rheology of the solution, keeping the salt and xanthan concentrations constant; then, the influence of temperature and then the hydration time on the rheology of the mixture, keeping the concentrations of the components constant; finally, the interaction of the particles of the mixture through the Electrical Conductivity and the Zeta Potential, varying the concentration of nanoclay and hydration time. It was concluded, for hydrophobic clay, that the interactions between the components of the mixture do not stabilize; the temperature, the salts have no significant influence on the rheology of the mixture; nano clay in concentrations not exceeding 5% (m/v) interacts with the Minimum Shear Stress; the rheological parameters stabilize after 96h of hydration. As for hydrophilic clay, there is an improvement in the rheology of xanthan solutions for certain concentrations of nanoclay; the addition of nanoclay favors rheology in the xanthan mixture with increasing temperature; and the hydration time does not significantly affect the nanofluid rheology; that there is interaction between nanoclay and xanthan.
|
|
13
|
-
VANESSA GOMES MATOS
-
CONSUMER PROFILE MODELING FOR PERFUME ENGINEERING: PREDICTION THROUGH ARTIFICIAL NEURAL NETWORKS
-
Líder : REGINA FERREIRA VIANNA
-
MIEMBROS DE LA BANCA :
-
GEORGE SIMONELLI
-
PAULO ROBERTO BRITTO GUIMARÃES
-
REGINA FERREIRA VIANNA
-
SILVANA MATTEDI E SILVA
-
Data: 30-nov-2020
-
-
Resumen Espectáculo
-
The representation of models for the prediction of the consumer profile for the perfumery industry is a differential for the strengthening of relations between consumers and development sectors of the HPPC- Personal Hygiene, Perfumery and Cosmetics industry. In view of the importance of the theme and the scarcity of works published in the literature, this research project focused on the development of a model based on artificial intelligence to serve as a starting point for determining new perfume compositions for consumers, both in a individual and interest groups, according to their psychological profile and previous choices of commercial fragrances. The model developed in this study is based on artificial neural networks to correlate the variables related to the consumption profile (acceptance variables: love, like, dislike; indication of use variables: day, night, spring, summer, autumn and winter), consumer choices (consumption variables: having the perfume, wishing to have the perfume, having bought the perfume before), fragrance performance indicators (silage and projection), data regarding liquid-vapor balance
(odor values fragrances) and sensory information on odorous substances used in perfumery. A database was built composed of the variables of acceptance, indication of use, consumption, performance indicators and fragrance odor values. The data collection was carried out through a virtual perfumery library and a page specialized in fragrance supplies, using data scraping techniques: Web Crawling and Web Scrapping. Nine profile prediction models were tested with predetermined variations, totaling 66 artificial neural networks. Among the results indicated, an artificial neural network was chosen as the most representative for this database, in order to be able to predict any of the 22 variables from the rest, such as, for example, the acceptance of a fragrance from its skin longevity and time of year being used. The prediction proved to be adequate with an absolute mean error of 0.003%. Through the processed output variables, graphic relationships were established between each of the analyzed parameters, such as: indication of fragrance use in relation to the periods of the day and seasons, assessment of silage, longevity and the preferences of each consumer in relation to fragrances. The graphic relations obtained were validated using the principal component analysis method (PCA), which determined the mathematical correlations present in the entire data set. Subjective data, such as: intensity of olfactory chords and olfactory notes, which proved to be inadequate for numerical treatments such as neural networks and statistical analysis, were represented through pictorial infographics and word cloud creating a subjective model that relates the impact and distribution of the chords and notes of a perfume in each fragrance. The knowledge of new relationships between the aspects involved in consumer choice showed the applicability of the models and analyzes proposed for the prediction of the consumption profile, understanding of market demands, presenting potential to be used as a basis for a system of personalization of fragrances by groups or specific consumers. Keywords: Perfume Engineering. Fragrance. Artificial Neural Networks. MLFN. GRNN. PNN. PCA. HPPC. RESUMO A representação
|
|
14
|
-
JOÃO CARLOS FERREIRA LIMA
-
HYDRODYNAMIC EVALUATION AND MASS TRANSFER IN A FILLED ABSORPTION COLUMN TO THE ACETONE WATER SYSTEM.
-
Líder : LUIZ MARIO NELSON DE GOIS
-
MIEMBROS DE LA BANCA :
-
LUIZ CARLOS LOBATO DOS SANTOS
-
SILVANA MATTEDI E SILVA
-
LUIZ MARIO NELSON DE GOIS
-
JOSÉ JAILTON PEREIRA MARQUES
-
Data: 15-dic-2020
Ata de defesa assinada:
-
-
Resumen Espectáculo
-
The present study relates hydrodynamic data in a gaseous absorption column with glass Raschig rings. The objective of this study is the application of the column for the treatment of gases, as volatile organic compounds, describing the pressure drop behavior and parameter definitions for this application. For the analysis of these hydrodynamic parameters, a liquid-gas (water-air) system was studied, using Ergun's correlation for the dry bed test and the Prahl method for the wet bed test. With this system, the optimum operational conditions were determined (inlet flows of the liquid and gas phases). To compare the Prahl's method, a dimensional analysis of the column was performed, where an empirical equation was obtained to determine the pressure drop, where it was possible to have an average decrease in errors of 15%. Still on the hydrodynamic tests, it was possible to identify the flood point and the load point, and they are located between the molar air flow rates between 3.0 and 4.0 L / min, in all tests based on the method developed by Bianchini (2018). Three operating regions are determined and the critical point of operation, where the pressure difference in the column stabilizes. Finally, an empirical model was developed in order to correlate the pressure drop in the column with the operational parameters. After all hydrodynamic analysis, the experimental regions were determined using the response surface methodology (MSR) used in this process to evaluate the factors that influence the response variable of acetone concentration in water. Thus, a fractional statistical planning was carried out, plus three repetitions at the central point (PC), totaling 19 experiments, with the flow of the light phase (Qd), the flow of the heavy phase (Qc), temperature (T) and time (t) considered as independent variables. The response surface methodology, brought fundamental information that helped in the understanding of the operation's learning absorption process, as an example the significant profile of the interaction of the variables Qd and Qc, presenting a bigger jump, in comparison to the other combinations, of values of concentration, going from 0.002 g / g to approximately 0.005 g / g. Thus, by compiling the hydrodynamic study information together with the data obtained in the mass transfer used as the basis for collecting column behavior information, the future gas treatment project can be continued, as foreseen in the general research project.
|
|
15
|
-
SUELLEN GORDIANO DE OLIVEIRA CUNHA
-
PHOTOCATALYTIC DEGRADATION OF PHENOL ON IRON OXIDES SUPPORTED ON COAL
-
Líder : MARIA DO CARMO RANGEL SANTOS VARELA
-
MIEMBROS DE LA BANCA :
-
ALEXILDA OLIVEIRA DE SOUZA
-
CARLOS AUGUSTO DE MORAES PIRES
-
MARIA DO CARMO RANGEL SANTOS VARELA
-
SIRLENE BARBOSA LIMA
-
SORAIA TEIXEIRA BRANDAO
-
Data: 28-dic-2020
-
-
Resumen Espectáculo
-
Phenolic compounds are pollutants found in many natural waters, which should be eliminated due to their high carcinogenic potential. Several routes have been proposed for this removal but heterogeneous foto-Fenton reaction has been recognized as one of the most efficient methods. However, there are still some drawbacks to be overcame to make this process commercially viable, such as the development of a cheap and no toxic catalyst which could efficiently remove this pollutant without producing any other toxic compound. With this goal in mind, carbon-supported iron oxides catalysts were prepared in this work and evaluated in the photocatalytic degradation of phenol combined with hydrogen peroxide. Carbon was prepared from carbonization of sisal residues followed by physical activation with steam. Iron nitrate was then impregnated on the carbons to obtain catalysts with 5, 10, 15 and 20% w/w Fe. Samples were characterized by Fourier transform infrared spectroscopy, chemical analysis, X-ray diffraction, Mössbauer spectroscopy, Raman spectroscopy, specific surface area and porosity measurements, scanning electron microscopy, diffuse reflectance spectroscopy and temperature programmed desorption. The catalysts were evaluated at 34 °C and 1 atm, using an aqueous stream containing 500 ppm of phenol, kept under oxygen flow to simulate a natural lake. Crystalline phases such as octocarbon, rhombohedral carbon and graphite were found for all samples. For the iron-containing samples, hematite (a-Fe2O3), maghemite (g-Fe2O3), magnetite (Fe3O4), non-stoichiometric wustite (Fe0.918O), metallic iron (a-Fe) and iron carbide (c-Fe5C2) were also detected. The presence and the amount of each phase changed with iron content. Magnetite, wustite and metallic iron were produced by carbon monoxide, resulting from carbon oxidation by nitrate ions (from precursor). Carbon monoxide was also able to diffuse into carbon where it reacts forming iron carbide. Iron also decreased the ordering of carbons and this effect increased with iron amount, decreasing the defects related to sp3 hybridization and to the sp2 hybridization of graphite. The porosity of the catalysts also increased with iron amount, resulting in an increase of specific surface areas. The carbon surface was made of acid groups such as carboxylic, anhydride, lactonic, carboxylic and carbonyl anhydride, as well as basic groups (quinones). By impregnating iron on carbon, the quantity and the kind of functional groups vary depending on its content (5, 10 15 and 20%). The catalyst with 5% iron showed carboxylic, lactonic, phenolic and quinonic groups, while the catalyst with 10% iron showed carboxylic, lactonic and quinonic groups. On the other hand, the catalyst with 15% iron showed carboxylic, lactonic, anhydride, carbonylic, quinonic and phenolic groups and the one with 20% iron showed only lactonic, carbonyl and quinonic groups. The adsorptive capacity of the catalysts, as well as their activity and selectivity, were found to depend on iron amount and on the kind and amount of surface groups. All catalysts are able to efficiently remove phenol from aqueous streams, but the sample with 15% of iron is the most active and selective in phenol oxidation, removing all phenol in 60 min without producing toxic intermediate compounds.
|
|
|
Tesis |
|
1
|
-
FLAVIA CAVALCANTE SOUTO MENEZES RODRIGUES LOPES
-
DEVELOPMENT OF PHOTOCATALYSTS BASED ON SILVER NANOPARTICLES SUPPORTED IN TITANIUM NANOTUBES FOR ANTHRACE DEGRADATION
-
Líder : CARLOS AUGUSTO DE MORAES PIRES
-
MIEMBROS DE LA BANCA :
-
CARLOS AUGUSTO DE MORAES PIRES
-
MARIA DO CARMO RANGEL SANTOS VARELA
-
SORAIA TEIXEIRA BRANDAO
-
CAIO LUIS SANTOS SILVA
-
CESÁRIO FRANCISCO DAS VIRGENS
-
HADMA SOUSA FERREIRA
-
Data: 30-oct-2020
-
-
Resumen Espectáculo
-
Pollution of the environment by industrial effluents has been increased in the last decades, becoming a serious social and environmental problem. Frequently produced effluents contain toxic and biologically refractory pollutants, which are not removed by conventional treatment systems such as coagulation / flocculation, activated carbon adsorption, precipitation and biological degradation. Nanostructured or nanoporous porous materials have deserved prominence in the area of molecular separation, catalysis and gas sensing due to their high surface area, high porosity and regular distribution of pore size. Among the nanostructured materials, titanium dioxide-based nanostructures are worthy of note, given their outstanding characteristics, such as chemical stability, non-toxicity, low cost and high efficiency. In this work, we intend to evaluate the photocatalytic potential of nanostructures based on titanium dioxide in the degradation of anthracene, in a bench lake. In this way, titanium dioxide nanoestructures (TiO2 P25 and TiO2 sol-gel) were prepared, using alkaline hydrothermal synthesis at 120°C. To optimize the synthesis parameters, samples were synthesized at three different times. As a result of this, first phase of the work, the effects of the precursor and duration of the heat treatment on the photocatalytic properties of nanostructures. The catalysts obtained were characterized by FTIR, XRD, UV, MET and SEM, in order to investigate the properties of the materials produced and to define the most suitable treatment time to proceed in the next phases of the work. The results for the hydrothermal treatment time of 24 h showed a diameter of about 22.5 to 15.5 nm and tube length in the range of 230 and 557 nm respectively for the sol-gel precursor. This definition was important because the results show that the catalysts produced canbe applied in the photocatalytic process for the degradation of organic pollutants. However, other techniques will be evaluated to conclude and define the best time to be used, as well as the precursor.. In the other phases of the work, metal was impregnated for the nanostructures formed in the time of 24 h, then photocatalytic tests were performed in suspension and the material characterized by the same techniques. Finally, the catalysts that presented the best photocatalytic performance were immobilized in latex membrane, tested in the anthracene degradation reaction and also characterized by UV, TG and XRD techniques. The results show, for all phases, that the nanostructures formed from the precursor based on s-TiO2(solgel) showed a better photocatalytic activity, when compared with the nanostructures formed from the precursor p-TiO2( Commercial). This result can be clarified with the decrease of the bandgap facilitating the migration of electrons from the valence bankroll to the conduction band during the reactions, making the reaction time shorter and more efficient. Other techniques presented in chapter 4 of this paper confirm this result.
|
|
2
|
-
LAIO DAMASCENO DA SILVA
-
DIRECT AMOXIDATION OF GLYCEROL TO ACRYLONITRILLA ON BIFUNCTIONAL CATALYSTS
-
Líder : LUIZ ANTONIO MAGALHAES PONTES
-
MIEMBROS DE LA BANCA :
-
LEANDRO MARTINS
-
LUIZ ANTONIO MAGALHAES PONTES
-
RODRIGO BRACKMANN
-
ROGER THOMAS FRANCOIS FRETY
-
RONALDO COSTA SANTOS
-
Data: 16-nov-2020
-
-
Resumen Espectáculo
-
Increasing biodiesel production has been resulting in excessive amount of produced glycerol. This work studies the direct ammoxidation reaction from glycerol to acrylonitrile, evaluating the use of bifunctional molybdenum, antimony-additivated and niobium-aluminium-oxide catalysts. The study was divided into three parts: catalysts containing different concentrations of aluminium-oxide-supported molybdenum, bimetallic catalysts containing aluminium-oxide-supported antimony and molybdenum, and a catalyst containing niobium-aluminium-oxide-supported molybdenum. Different metal composition and support on catalysts was chosen in order to effect caused by the combination of acid/redox properties, aiming the development of a more acrylonitrile selective catalyst. Catalysts synthetized by wetness impregnation were characterized by X-ray Fluorescence (XRF), X-ray Crystallography (XRC), Fourier-transform Infrared Spectroscopy (FTIR), Nitrogen adsorption-desorption, morphological analysis by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Temperature-Programmed desorption with Ammonia (NH3-TPD) and Temperature-Programmed Reduction with hydrogen (H2-TPR). Catalytic evaluation was conducted on a fixed-bed continuous-flow reactor under a NH3, glycerol and synthetic air at 1 atm and 400°C. Acrylonitrile formation was observed for all studied catalysts. Among the catalysts with different concentration of aluminium-oxide-supported molybdenum, 10,0 % Mo/ γ-Al2O3 with yield in 19 % of acrylonitrile. Among bimetallic catalysts containing aluminium-oxide-supported antimony and molybdenum, the MoSb/γ-Al2O3 (2/1) resulted in the best performance: 25 %. Finally, the catalyst containing niobium-aluminium-oxide-supported molybdenum (Mo/Nb2O5/Al2O3) was the one that shoed the best results of all: 31% of acrylonitrile production.
|
|
3
|
-
YAIMÉ DELGADO ARCAÑO
-
CONVERSION OF XYLOSE INTO XYLITOL FROM CORNCOB
-
Líder : LUIZ ANTONIO MAGALHAES PONTES
-
MIEMBROS DE LA BANCA :
-
LUIZ ANTONIO MAGALHAES PONTES
-
LEILA MARIA AGUILERA CAMPOS
-
LEONARDO SENA GOMES TEIXEIRA
-
DALMO MANDELLI
-
MARCO ANDRÉ FRAGA
-
WAGNER ALVES CARVALHO
-
Data: 26-nov-2020
-
-
Resumen Espectáculo
-
The increase in the xylitol demand in the food and pharmaceutical market, as well as the possibility of its use as a raw material of renewable origin to form other compounds of interest, such as ethylene glycol, propylene glycol, lactic acid, furans, among others, have motivated an increase in research to obtain this polyalcohol. Industrially, xylitol is produced by catalytic hydrogenation of xylose, in the presence of a metallic catalyst and under high temperature and pressure of H2. The use of biomass residues as a source of xylose, and the obtaining of xylitol through consecutive reactions in a single reactor allows greater economic competitiveness. In this work, the production of xylitol from pure xylose and fresh corncob was studied, since this residue has a high xylose content (31%), low cost, and high availability. The acid hydrolysis step was optimized, reaching 93% in the percentage of xylose extraction working at 140 ºC, 1.3% H2SO4 for 5 min. The best hydrogenation conditions were 0.1 g of 5% Ru/C, at 140 °C, and 600 rpm, reaching 98% xylitol yield, using a 5% Ru/C commercial catalyst. The hydrolytic hydrogenation of fresh corncob under mild conditions (H2SO4 0.5%, 140 °C, 2 Mpa H2) led to a xylitol yield of 70.8%. The process proved to be effective for the production of xylitol directly from the biomass residue, opening perspectives for reducing its production costs, and implementing the new process in a biorefinery.
|
|