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Dissertations |
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1
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LETÍCIA SILVEIRA
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PRODUCTION OF ALGINATE BIOFILM ADDED VANILLIN FOR APPLICATION AS BIO-CURATIVE
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Advisor : RENATA CAROLINA ZANETTI LOFRANO
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BANKING MEMBERS :
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RENATA CAROLINA ZANETTI LOFRANO
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CRISTIANE MEDINA FINZI QUINTAO
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MATEUS DE SOUZA AMARAL
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Data: Jan 13, 2022
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Show Abstract
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The use of biopolymers from renewable resources is highly studied and they are, in general, biodegradable, biocompatible and can be obtained at low cost. Biopolymers have many applications, for instance in health, known as biomaterial. In this way, this work aims to synthesize a biopolymer of alginate and vanillin using glycerol and calcium chloride as plasticizer and crosslinking agent, respectively. Using design of experiments, different biopolymers were produced and analysing the solubility and the swelling degree, the best region, regarding the application, was found, corresponding to the one using vanillin at concentration up to 0.015 g, and the calcium chloride, values higher than 0.090 g, obtaining films with solubility around 30 % and the swelling degree between 100 and 120 %. Regarding the process optimization it is concluded that the NBI method can analyze concave regions, predicting the optimal points and generating the Pareto chart with equispaced boundaries. The antimicrobial test allowed to observe the antimicrobial activity of the validated films in the optimization, as well as vanillin solution with calcium chloride and glycerol, comparing the results with the control film, obtaining an innibition halo only in the presence of vanillin. Thermal analyses of thermogravimetric analysis and differential scanning calorimetry demonstrated that the material has thermal stability. The biofilm produced shows potential for application as a biomaterial.
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2
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EDUARDO ZANITTI ÁVILA COUTO
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COMBUSTION OF ACRYLONITRILE ON CATALYSTS (Cu or Ce)-OXIDE and (CuO or CeO2)-BETA
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Advisor : MARCELO DA SILVA BATISTA
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BANKING MEMBERS :
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ANDRÉ GUSTAVO SATO
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JORGE DAVID ALGUIAR BELLIDO
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MARCELO DA SILVA BATISTA
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Data: Mar 5, 2022
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Show Abstract
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The emission of acrylonitrile resulting from its production generates serious environmental problems and consequently to human health. Selective catalytic oxidation has been shown to be a relevant method for solving this problem, being more efficient than conventional combustion. This method consists of the use of catalysts capable of reducing the activation energy of the reaction and selecting the desired product, minimizing as much damage as possible to the damage caused in the process. In this work, CuO, CeO2, CuO-BETA catalysts were used in the selective catalytic oxidation of acrylonitrile in order to decrease the operating temperature (<800ºC) and preferably produce N2, mitigating environmental damage. The mass catalysts of CuO and CeO2 were obtained commercially while the supported CuO-BETA was prepared by the incipient impregnation method. Subsequently, the four catalysts were characterized by XRD, TPR-H2 and UV-Vis spectroscopy. XRD results showed characteristic peaks of copper oxides (CuO) and cerium (CeO2) in the mass and supported catalysts. The addition of these oxides to the support by the incipient impregnation method did not alter the morphology of zeolite-BETA. TPR-H2 profiles indicated that the copper oxide supported in beta zeolite led to a decrease in the temperature of reduction of copper species. UV-Vis spectroscopy analyses identified the presence of Cu2+ions, [Cu-O-Cu]2+ and Ce4+, as well as CuO nanoparticles in the CuO-BETA catalyst. The catalytic assays showed that the catalysts present good activity for the selective oxidation of acrylonitrile, causing a significant decrease in reaction temperature, ceo2 being the most promising among them for presenting lower reaction temperature and higher selectivity for N2 and CO2 formation.
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3
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MARCELA MAGALHAES DE PAULA
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INFLUENCE OF THE POLYMERIC PRECURSOR ON THE SYNTHESIS VIA ONE STEP POLYMERIZATION OF CuO/CeO2 CATALYSTS AND EVALUATION IN SELECTIVE CATALYTIC OXIDATION OF ACETRONITRILE
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Advisor : JORGE DAVID ALGUIAR BELLIDO
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BANKING MEMBERS :
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JORGE DAVID ALGUIAR BELLIDO
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MARCELO DA SILVA BATISTA
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ADRIANO LOPES DE SOUZA
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Data: Jun 29, 2022
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Show Abstract
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Given the growing concern about air pollution caused by the emission of greenhouse gases and volatile organic compounds, such as ammonia, carbon monoxide and nitrided gases, several alternatives have emerged to contain it. In view of the technologies already implemented, in the present work selective catalytic oxidation was applied to treat acetonitrile on CeO2 supports and CuO/CeO2 catalysts synthesized by the one-step polymerization method. In which the focus was to evaluate the influence of the complexing agent, varying the acids, in citric, malic and oxalic, and the presence of copper II in the final properties of the catalysts. As well as the catalytic performance during the reaction and their respective selectivities in N2 and CO2 production. Finally, the effects of these variants on the formed materials were investigated through physical characterization techniques, such as Thermogravimetric Analysis (ATG), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Physisorption with N2 (B.E.T. method), Scanning Electron Microscopy (SEM), Programmed Temperature Reduction (TPR-H2) and Temperature Programmed Desorption (TPD-CO2). From the XRD diffratrograms, the presence of CeO2 in the prepared catalysts was identified, it was also noted that the deposition of CuO in the synthesized materials did not change their structure. Physisorption analyzes with N2 provided isotherm profiles that varied between supports and catalysts, in addition to demonstrating that those synthesized with oxalic acid (CeOx and CeOxCu) had the highest specific areas, compared to those with malic acid (CeMa and CeMaCu). and citrus (CeCi and CeCiCu). Since these presented larger volumes and pore sizes as evidenced in the BET, these properties were related to the stability of their polymeric chains demonstrated by the ATG. Furthermore, in catalytic tests conducted in the range of 100-600 °C for 1 hour, 100% conversion of acetonitrile was identified for all supports and catalysts at temperatures below 350 °C. With high selectivity in N2 and CO2 for CeMa and CeMaCu.
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4
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Carla Cristina Araujo Parreira
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DEVELOPMENT OF A NEW EQUATION FOR FORECAST PARAMETERS OF NUCLEAR FISSION REACTORS FROM DYNAMIC MODELING AND SIMULATION
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Advisor : JUAN CANELLAS BOSCH NETO
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BANKING MEMBERS :
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JUAN CANELLAS BOSCH NETO
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EDSON ROMANO NUCCI
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MARCELO CARDOSO
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Data: Jul 7, 2022
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Show Abstract
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The viability of nuclear reactors depends on an efficient safety system in the operation of nuclear processing units. Much of the safety of nuclear fission reactors is related to the neutron density that requires a well-balanced balance between the emitted neutrons and the lost neutrons (via neutron absorption or leakage), in order to avoid major damage such as overheating and possible explosions. In the present work, a literature review on nuclear energy, dynamic modeling and simulation of a nuclear reactor and the development of a new equation (system of non-linear differential equations) for prediction of neutron density, power and fractions was carried out. delayed neutron precursor groups in a nuclear fission reactor and application of fuzzy logic. According to the literature, the system of nonlinear differential equations proposed by Duderstadt and Hamilton is one of the most representative for the prediction of neutron density, but it has a deficiency in the result of neutron density in moderate systems. In this work, the Duderstadt and Hamilton equation was modified with the insertion of new terms in the neutron density, power and concentration equations of the delayed neutron generator groups, generating a system of seven nonlinear differential equations that were solved by the Runge Kutta method. fourth order in the OCTAVE free software. From the proposed model, dynamic simulations of fission nuclear reactors were performed. The simulations resulted in the neutron density, the reactor power estimation and the estimation of the mass fractions of the late neutron precursor groups. The validation of the new proposed model was performed by superimposing the plotting of simulation results on the plotting of experimental data from the literature for the PWR TRIGA reactor at CDTN/UFMG. Through Fuzzy Logic, it was possible to perform a numerical estimate in relation to the percentages of neutrons in the Reactor. With this analysis, we obtained a value of approximately 60% of neutrons that must be emitted by the primary source in the Reactor and 41% of neutrons that must be absorbed by the moderators. The new equation proposed by the author resulted in an adequate compatibility between the proposed model and the experimental data. This new equation is an important tool for the design of control systems for nuclear fission reactors, representing an interesting suggestion for future work.
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5
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Matheus Furlan Pinheiro
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DEVELOPMENT OF A NANOBUBBLE GENERATOR PROTOTYPE FOR A FLOTATION PROCESS ASSOCIATED WITH THE DEVELOPMENT OF A MODIFIED STARCH-BASED DEPRESSOR
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Advisor : FABIANO LUIZ NAVES
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BANKING MEMBERS :
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EDUARDO PRADO BASTON
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FABIANO LUIZ NAVES
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JOSÉ IZAQUIEL SANTOS DA SILVA
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RENATA CAROLINA ZANETTI LOFRANO
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Data: Nov 11, 2022
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Show Abstract
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The reduction of high iron content reserves and the need for economic use of all extracted mineral resources, makes the separation of fine and ultrafine ore a reason of important research resources. Flotation is the unit operation most used in the separation of particles of granulometry between 10 μm and 300 μm, but the comminution present in the initial stages of processing, produces smaller particles, commonly discarded in the form of wet or dry tailings. In this context, the use of micro and nanobubbles in reverse cationic flotation, with gelatinized starch as a depressant, has been tested in order to increase the recovery of this particulate by different mechanisms. This work seeks to evaluate the influence of the use of micro and nanobubbles in the reverse cationic flotation process, of iron ore processing waste, together with the use of starch modified by an association of thermal and alkaline treatment, with Ammonium Hydroxide. For the bubbles generation, a pumping system was built, using a venturi tube for air suction, in the pump suction, and subsequent pressurization of the system at 5 bar, in a saturation vessel. Design of experiments (DOE) was applied for modeling a Response Surface Designd CCD) and process optimization through the Normal Boundary Intersection (NBI) algorithm, obtaining parameters of maximum recovery of iron ore fines.
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6
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Gabriela Martins de Paiva
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PRODUCTION OF BACTERIAL NANOCELLULOSE FROM WASTE BREWER'S YEAST FOR ADSORPTION OF Cu(II), Fe(III), Ni(II) and Co(II) FROM MINING EFFLUENTS
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Advisor : IGOR JOSE BOGGIONE SANTOS
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BANKING MEMBERS :
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IGOR JOSE BOGGIONE SANTOS
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EDSON ROMANO NUCCI
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FERNANDA PALLADINO PEDROSO
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RITA DE CASSIA SUPERBI DE SOUSA
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Data: Nov 29, 2022
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Show Abstract
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Brazil is one of the main producers and exporters of iron ore in the world, with a production of 358.0 million tons in the year 2021. Due to the large volume of production, there is, consequently, the generation of a large volume of liquid waste that needs be treated before being disposed of in the environment, as they have a high content of heavy metals. However, the treatments, hitherto known, are expensive and complex. An economical and environmentally viable alternative for the treatment of these residues is the use of bacterial nanocellulose as an adsorbent of the heavy metals present in the composition of the residues, due to its properties of biocompatibility and biodegradability. However, further studies are needed to increase production efficiency, changing fermentation parameters and evaluating the use of alternative substrates. The Brazilian brewing industry produces around 14.0 billion liters of beer a year and, with that, a large volume of nutritionally rich waste. With its high nutritional value, the residues are excellent substrate candidates for bacteria producing bacterial nanocellulose, adding value to them. Given this scenario, the present research project aims to (i) the static production of bacterial nanocellulose using the brewing industry waste as a substrate, (ii) the obtainment of an adsorbent composed of bacterial nanocellulose for the treatment of waste from the mining industry and (iii) recovery of heavy metals and iron oxide from mining industry effluents for reuse in industries. It was possible to obtain approximately 1532 mg of bacterial nanocellulose through the batch system. As an adsorbent, the material showed to be very promising, obtaining a maximum adsorption capacity for the metals Co (II), Ni (II) and Cu (II) of, respectively, 0.0739, 0.2504 and 0.3945 mg· g-1. For the same metals, the removal rate of the synthetic solutions studied was, respectively, 62.56, 39.13 and 61.64%
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7
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Fernanda Carlos Monteiro
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EVALUATION OF ENERGY INTEGRATION OF A BIOREFINERY AIMING FOR THE PRODUCTION OF SECOND GENERATION ETHANOL USING PINCH ANALYSIS
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Advisor : BOUTROS SARROUH
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BANKING MEMBERS :
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BOUTROS SARROUH
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RENATA CAROLINA ZANETTI LOFRANO
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FERNANDO MASARIN
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Data: Nov 30, 2022
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Show Abstract
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The use of sugarcane bagasse for the production of second-generation ethanol is a viable alternative for the destination of bagasse that is not all used within a sugarcane plant, as it adds value to this residue. About 280.33kg/h of sugarcane bagasse generates a total of 886.23kg of ethanol after
12 hours of operation. With the addition of heat exchangers in the second generation ethanol production flowchart proposed in this work, it was possible to reduce the consumption of hot and cold utilities by 23.60% and 48.84%,
respectively. With the reduction of utilities, production costs and environmental impacts are also reduced, making production more advantageous when compared to production in which there is no heat exchanger
present to help preheat or pre-cool system equipment.
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8
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KEIVY EVILÁZIO GOMES
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APPLICATION OF FUZZY LOGIC IN QUALITY CONTROL IN BEER PRODUCTION
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Advisor : EDSON ROMANO NUCCI
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BANKING MEMBERS :
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EDSON ROMANO NUCCI
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JUAN CANELLAS BOSCH NETO
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ALESSANDRA COSTA VILACA
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ANDRE AGUIAR MENDES
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Data: Dec 1, 2022
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Show Abstract
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The brewing sector, due to the increase in production activity and the more demanding taste of the consumer, has sought to improve the quality of the beer produced, having even used artificial intelligence methodologies to deal with the uncertainty, subjectivity and complexity associated with this type of bioprocess engineering problem. The Fuzzy system is one of those methodologies that, in addition to generality, expressive power and the ability to model real-world problems, act to circumvent the imprecision implicit in decision-making problems. Thus, this research aimed to develop two decision support systems through a Fuzzy system. The first Fuzzy system was developed to evaluate the quality of Pilsen beer, and the second Fuzzy system aimed to identify different types of beer. The methodology involved collecting user information about the following types of beer: Pilsen, Wheat, Stout and IPA. The system was developed using Scilab® and INFUZZY Software and the input variables for the first decision support system were CO2, color, density, pH and alcohol content, and the response variable was beer quality. . The developed system had a hit rate above 90% for beer approved for consumption and 85% for beer that was not approved. In addition, considering simulated scenarios, the second Fuzzy system correctly predicted, more than 99% of the time, the alcohol content, color and density of the beer produced, indicating to the user the type of beer chosen.
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9
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Lívia Mara Cândido
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RECOVERY OF NIOBIUM FROM TAILINGS GENERATED
THROUGH THE PROCESSING OF APATHIC ORES
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Advisor : JUAN CANELLAS BOSCH NETO
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BANKING MEMBERS :
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JUAN CANELLAS BOSCH NETO
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DEMIAN PATRICK FABIANO
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EDSON ROMANO NUCCI
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MARCELO CARDOSO
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Data: Dec 2, 2022
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Show Abstract
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Brazil has one of the world's largest reserves of niobium. In apatite beneficiation processes, niobium minerals are often found and have an extremely fine granulometry and are commonly disposed in a dam. The objectives of this work were: to evaluate, through the kinetic study of flotation, the metallurgical recovery rates of niobium ore for different granulometric ranges and to use the response surface techniques and statistical design of experiments. In this context, samples were collected from the apatite processing tailings streams that have a high niobium content and incorporated into the samples for niobium flotation. Bench flotation tests were carried out and a subsequent kinetic adjustment was carried out, based on the accumulated metallurgical recovery data. An experimental design of the type Central Composite Rotational Design (CCRD; Central Composite Rotational Design) was initially used, which is part of the response surface methodology (RSM; Response Surface Methodology), with the proposal of finding the optimal points of the main variables, given the simultaneous analysis of the three response variables. As a result, the highest value found for the kinetic constant was 0.0195 s-1, corresponding to granulometry below 37μm. When using the response surface technique, with the optimization of the variables, a metallurgical recovery of 70% was obtained for the granulometric range below 37μm. It is concluded that for the optimization of the niobium flotation process, the granulometry must be kept below 37μm and above 5μm, so that significant losses do not occur in the process. The optimization of the results and the collector dosage factors, pH and surfactant/collector partition to be considered optimal were 881 g/ton, 6.7 and 24%/76%, respectively
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10
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Paula Maricele da Silva
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SYNTHESIS OF GEOPOLYMERS PRODUCED FROM ALUMINOSILICATE FROM AMPHIBOLITES FOR APPLICATION IN CIVIL CONSTRUCTION
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Advisor : FABIANO LUIZ NAVES
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BANKING MEMBERS :
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FABIANO LUIZ NAVES
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GISELLA ROSSANA LAMAS SAMANAMUD
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MARIANA ARRUDA PEREIRA
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MATEUS DE SOUZA AMARAL
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RENATA CAROLINA ZANETTI LOFRANO
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Data: Dec 7, 2022
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Show Abstract
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Geopolymers are inorganic macromolecules produced by alkaline activation of aluminosilicate materials. Its use in civil construction is a promising alternative to replace Portland cement (PC), whose manufacture is responsible for 7% of CO2 emissions on the planet. In addition, the production of geopolymers is environmentally sustainable, as its raw material is industrial waste that can be used and recovered, rather than being discarded. For the development of the geopolymer, a precursor is needed, such as an aluminosilicate mineral, and an alkaline activator, such as NaOH or sodium silicate. This work aimed to analyze the mechanical properties of a geopolymer produced from niobium mining waste, especially the amphibolite rock, used as a precursor. According to the Extreme Vertices mixture experimental design methodology, specimens were prepared with different molar ratios of SiO2/Al2O3, Na2O/SiO2 and H2O/Na2O, under curing conditions at room temperature. The samples were submitted to axial compressive strength and tensile strength tests. The results obtained in the response surface contour region ranged from 0.04 to 0.26 MPa for tensile bond strength and from 0.7 to 1.96 MPa for compressive strength. The interpretation of the generated response model indicated optimal values of proportions of NaOH, SiO2 and water for the experiment performed. The values were close to those established by technical standards for mortars and cements (ABNT, 2005). Therefore, it is argued that viability of amphibolite as a geopolymer and raw material in civil construction.
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11
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Renan Gabriel Condé Santos
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SYNTHESIS AND CHARACTERIZATION OF MIXED MATERIAL OF EUCALYPTUS CHARCOAL AND ALUMINUM BY THE SOL-GEL METHOD
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Advisor : ALEXANDRE BOSCARO FRANCA
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BANKING MEMBERS :
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ALEXANDRE BOSCARO FRANCA
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EDUARDO PRADO BASTON
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FABIANO LUIZ NAVES
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MATEUS DE SOUZA AMARAL
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Data: Dec 14, 2022
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Show Abstract
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Charcoal has flexibility in its applications, being able to compose from components for pigmentation of paints to, when going through an activation process, to be applied in catalytic and adsorptive processes. Subsequently, the coal can undergo thermal and chemical treatments, such as calcination and impregnation, to further optimize its characteristics. A synthesis process currently studied is the sol-gel process, in which a colloidal solution is used that rapidly precipitates forming a gel and, being heat treated, can generate a micro or meso-porous material, increasing its specific area. This work aimed to develop a support for a catalyst based on charcoal and alumina, which was synthesized in the charcoal pores by the sol-gel method using steam in the hydrolysis step. The synthesis inside the pores can be verified by a set of analyzes such as: XRD, where it was possible to assume the presence of structures of pseudoboehmite and γ-alumina; Thermogravimetry indicated a reduction in mass loss for the treated coal due to the thermal stability of the alumina; Physisorption of N2 indicated an increase in specific area (8.97%) and total pore volume increased (9.48%) in relation to untreated coal; SEM/EDS confirmed the presence of aluminum oxide inside the walls of the pores of the coal, as well as on its surface, which could be observed due to the magnification of the sample and by energy dispersive X-ray spectroscopy. Therefore, in the tests carried out, there is a strong indication of the production of the mixed material of coal/alumina sol-gel object of study of this work.
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12
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Bruna Paloma Ribeiro
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IMMOBILIZATION OF MICROORGANISMS IN CARRAGEENA SPHERES
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Advisor : DEMIAN PATRICK FABIANO
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BANKING MEMBERS :
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DEMIAN PATRICK FABIANO
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EDSON ROMANO NUCCI
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JUAN CANELLAS BOSCH NETO
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CÍNTHIA MARIA FELÍCIO
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Data: Dec 22, 2022
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Show Abstract
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The present work aimed to synthesize carrageenan spheres and to immobilize microorganisms in their polymeric structure. Two yeasts Saccharomyces pastorianus and Saccharomyces cerevisiae with immobilized microorganisms were chosen. The immobilized yeasts were tested in fermentation using three different substrates: brown sugar, crystal sugar and D(+)sucrose. The synthesis of the carrageenan sphere was achieved when there was a combination of the concentrations of two solutions: the carrageenan solution, at a concentration of 10 g.L-1, and the KCl solution, at a concentration of 0.848 mol. L-1. At these same concentrations, it was possible to immobilize the yeasts in the carrageenan polymeric matrix and form spheres. The results of the fermentations with immobilized yeasts show that the consumption of sugar occurs by two factors: by the adsorption of sugar in the polymeric matrix of the carrageenan, due to the electrostatic interactions between them and also by the consumption of sugar by the immobilized yeasts. Sucrose was the best sugar to use as a substrate. Regarding the microorganisms, it can be noted that Saccharomyces cerevisiae obtained more satisfactory results, due to the greater speed and greater consumption of sugar, in comparison with the other yeast. This higher consumption can be explained by the greater amount of viable cells present within the spheres. In addition, the spheres were dried with immobilized yeasts in the desiccator, in an oven and naturally. However, the cells after rehydration of the beads are not viable. In view of all this, it can be concluded that microorganism cells can be immobilized in carrageenan spheres, however, the immobilization process must be refined to increase cell viability. In addition, immobilized cells can be used and reused in biotechnological processes to produce products of interest.
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