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    Tratamento de águas contaminadas com glifosato mediante adsorção e eletrólise acopladas
    (Universidade Federal de Goiás, 2023-06-23) Pereira, Érica de Mendonça; Léon, José Joaquín Linares; http://lattes.cnpq.br/5126547270872842; Léon, José Joaquín Linares; Souza, Fernanda de Lourdes; Silva, Fabricio Machado
    Glyphosate is a wide-spectrum herbicide extensively used in Brazil and worldwide. Its presence in surface and ground water has alerted to the need for alternative removal treatments, since it is a refractory pollutant to conventional water and wastewater treatments. Among the alternative treatments, electrochemical advanced oxidation processes emerge as an option. Nevertheless, these processes are often limited by mass transportation, owing to the low concentration of the target molecules found in hydric bodies. This makes necessary the addition of pre-concentration stages for the ulterior electrochemical treatment. The present work brings a possible alternative by the combination of a previous pollutant accumulation process by active carbon adsorption, followed by the electrochemical regeneration of the pollutant adsorbed to, again, reinitiate a new cycle. In the study of glyphosate adsorption onto activated carbon, the effects of pH and ionic strength were investigated. In the electrochemical regeneration, the effect of current density and the reuse of the adsorbent for multiple treatment cycles were evaluated. Results indicated satisfactory pollutant retention capacity by the adsorbent, especially under acid pH and absence of electrolytes (36 mg g-1). Furthermore, the electrochemical regeneration demonstrated the ability to achieve total mineralization of the pollutant in anodic oxidation on boron-doped diamond electrode and maintenance of 89%, on average, of the specific surface area of the adsorbent after five adsorption/regeneration cycles.
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    Avaliação da atividade hemaglutinante e antibacteriana dos extratos proteicos intracelulares e extracelulares de bactérias isoladas a partir de corais marinhos
    (Universidade Federal de Goiás, 2023-03-30) Pereira, Thairyne Naruan Alves; Castiglioni, Gabriel Luis; http://lattes.cnpq.br/6050198962131737; Castiglioni, Gabriel Luis; Vendruscolo, Francielo; Guillo, Lidia Andreu
    For decades, the terrestrial environment was the center of studies, however, research was extended from the terrestrial to the marine scope, in order to discover new molecules. Corals are marine animals that are present in seas, oceans and marine nurseries. These animals can live in symbiosis with several organisms, including bacteria that produce molecules of high biotechnological interest. From the collection, isolation and cultivation of these organisms, it is possible to obtain molecules of biotechnological interest. In this context, this study aims to isolate bacterial colonies from marine corals, evaluate the hemagglutinating activity and antibacterial activity of intracellular and extracellular protein extracts from bacterial colonies isolated from Green Star Polyps and Xenia Pompom corals, and obtain the protein profile of the extracts from SDS-PAGE electrophoresis. Eighteen colonies of bacteria were isolated, 9 colonies from each coral. Crude extracts were obtained from the cultivation of isolated bacteria in two different culture media, which were subsequently subjected to 60% saturation with ammonium sulfate. For the hemagglutinating activity, only the extracellular extracts showed activity, which allows inferring that they may contain proteins that have different biological activities, such as antibacterial and antiviral. Therefore, carbohydrate inhibition was performed, however, there was no inhibition of hemagglutinating activity for the following sugars tested, galactose, fructose, maltose, glucose, xylose, rhaminose and sucrose. Therefore, these extracellular extracts were subjected to antibacterial activity, which was determined by the Minimum Inhibitory Concentration (MIC) method, by the broth microdilution technique, against the microorganisms Escherichia coli, Staphylococcus aureus, Bacillus cereus, Salmonella typhimurium, and Enterococcus faecalis. There was antibacterial activity of three (E1 G13, E2 G13 and E2 P2) of the four protein extracts against Enterococcus faecalis. Protein extracts E1 G13, E2 G13 and E1 P2 showed inhibition of microbial growth against another strain tested, obtaining a concentration of 1000 µg.mL-1 for Escherichia coli. The four extracellular protein extracts obtained hemagglutination for the three blood types tested and are promising antibacterial agents, which can contribute to the expansion of natural products of marine origin.
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    Avaliação da composição mineral do mosto de cana de açúcar no desempenho fermentativo com cultura mista de leveduras Saccharomyces cerevisiae diagnóstico e solução de problemas relacionados a produção industrial de etanol
    (Universidade Federal de Goiás, 2022-12-16) Silveira, Larissa Gabriele Silva; Freitas, Fernanda Ferreira; http://lattes.cnpq.br/0883086742146577; Castiglioni, Gabriel Luis; http://lattes.cnpq.br/6050198962131737; Castiglioni, Gabriel Luis; Vendruscolo, Francielo; Ribeiro, Eloizio Júlio
    The International Energy Agency estimates that ethanol from sugar cane reduces the emission of greenhouse gases by 89%. Brazil ranks second in world production of ethanol but still needs to improve in the coming years to reach the decarbonization targets proposed by the National Biofuel Policy. However, the process is consolidated the ethanol production improvement depends on the role performed by several factors as fermentation. Industrial yeasts are inoculated in the fermentation owing to their great fermentation characteristics but it may happen the entrance or appearance of contaminating microorganisms which are called wild yeasts. The process requires a wide range of minerals to reach adequate efficiency and a correct range of macro and micronutrients in the fermentation may improve the functioning of cellular metabolism and prevent the development of wild yeasts. This study aims to analyze the effects of mineral nutrients on ethanol production from synthetic sugarcane juice and a mixed culture of industrial and wild yeast. The industrial yeasts BG-1, CAT-1, FT-858L and PE-2 of the species Saccharomyces cerevisiae were used and the wild yeast was isolated from an Alcohol Power Plant in Goiás and called LFS. The yeasts were identified according to their macromorphological characteristics in the growth of colonies on plates. To assure the experimental reproducibility the synthetic sugarcane juice was used with 16% of sugars (m/v). The fermentation essays were evaluated by high performance liquid chromatography and residual sugars, glycerol, ethanol and acetic acid quantified. Minerals were quantified by atomic absorption spectrometry. The tests were carried out in the proportion of 30% of the wild yeast and 17.5% of each industrial yeast for 72 hours at 30ºC with 2.5 mL of the synthetic sugarcane juice. The inoculum was prepared from the scraping of the yeast present in the sterile plates and the solution mineral was added for the supplementation. The influence of Ca, Fe, Cu, K, P, N, S and Mg ions was evaluated at the end of fermentation through colony population dynamics, sugar residual and ethanol production. The tests showed that nitrogen, magnesium, sulfur and copper favor fermentation while calcium, phosphorus and iron are more prejudicial to the process. To evaluate the relationship between the prejudicial minerals was carried out a simplex-lattice mixture design with 3 components and results showed that excess calcium is prejudicial to ethanol production. Another simplexcentroid mixture design was carried out with the 4 elements identified as favorable in synthetic sugarcane juice with calcium excess and the contamination decreased by 67% with supplementation of nitrogen, magnesium and sulfur. Tests in natural sugarcane juice showed that reduction of contaminating was by 48% and confirmed that nitrogen, magnesium and sulfur are favorable to inhibit wild yeast growth. In conclusion, the tests demonstrated that supplementation of nitrogen, magnesium and sulfur reduces the contamination and increases ethanol production. As a suggestion, the addition of fertilizers with these minerals during the cultivation of sugarcane or in start fermentation may help to improve the industrial process.
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    Análise termodinâmica do processo de pirólise de microalga a partir do cálculo de equilíbrio químico e de fases simultâneo
    (Universidade Federal de Goiás, 2021-05-13) Viegas, Júnnio de Sousa; Souza, Thiago Leandro de; http://lattes.cnpq.br/7431199944070783; Souza, Thiago Leandro de; Silva, Simone Monteiro e; Corazza, Marcos Lúcio
    In a scenario where population growth is exponential, the supply of the energy matrix is finite, the processing and use of current sources are extremely harmful to the environment, a new name is pointed out as a sustainable energy source to supply all these issues: microalgae biomass. This is particularly interesting due to its high growth rate, high productivity, adaptability to different habitats, non-competitiveness with agriculture and the results of its processing can be used to produce biofuels, products of high added value of industrial interest, treatment and soil recovery. In addition, we may subject it to a decomposition process to obtain your products (bio-oil, gas and charcoal). In addition, it can be subjected to a decomposition process to obtain its products (bio-oil, gas and charcoal). In this study, a thermodynamic analysis of the pyrolysis of microalgae biomass was carried out, which consists of processing the biomass at high temperatures in the absence or low presence of oxygen. From this work, data were obtained that represent the behavior of the reaction system in chemical and phase equilibrium for different operating conditions, varying temperature and humidity, in which the conditions in which the required products are found in greater and/or less quantities. The method for calculating the chemical and phase simultaneous equilibrium explored was Gibbs minimization, under constant temperature and pressure conditions, by a non-stoichiometric approach. A mixture-model composed of palmitic acid, glucose and glutamic acid was considered to represent the biomass of microalgae. The possibility of forming a liquid phase, simulated by the UNIFAC thermodynamic model, was investigated, using the stochastic particle swarm optimization method, in which the possibility of forming 3 distinct phases was considered, one phase behaving as a mixture of ideal gases, a liquid phase and another solid phase modeled as pure solid carbon. The minimization model was also implemented in the GAMS® software, General Algebraic Modeling System, using the CONOPT non-linear programming solver, in which only formation of solid and gaseous products was considered. The studied pyrolysis reaction was predominantly exothermic, with heat of reaction varying from approximately -32 to -16 kJ/mol. For the studied conditions, there was no prediction of liquid phase in the reaction system. Gaseous products such as H2 and CO2 showed maximum yield, 0.246 and 0.415 mol per mol of carbon fed respectively, both under maximum operating conditions for humidity and temperature, under the same conditions there was a greater potential for thermal energy generation, evaluated by the total heating value.
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    Produção de hidrogênio a partir de efluente do processo de fabricação de biodiesel
    (Universidade Federal de Goiás, 2022-12-21) Teixeira, Isabela Rodrigues; Andrade, Laiane Alves de; http://lattes.cnpq.br/6777831109573242; Alonso, Christian Gonçalves; http://lattes.cnpq.br/7285754665946583; Alonso, Christian Gonçalves; Andrade, Laiane Alves de; Souza, Thiago Leandro de; Oliveira, Sérgio Botelho de; Souza, Guilherme Botelho Meireles de
    The growing energy demand witnessed stems from the way industrial production processes developed from 1970 onwards with the so-called new industrial revolution. This high demand provoked an escalation in the production of fuels, having been supplied, since then, mainly by fossil fuels. The use of this type of energy source results in the emission of compounds into the atmosphere such as Carbon Dioxide (CO2) and other gases that, if released in large quantities, cause environmental imbalances such as the global warming. Such a scenario reveals the need for an energy transition. The gradual transition from carbon-based fuels to low or no-emissions would contain a likely energy crisis. Recent studies indicate that hydrogen (H2) has great potential as one of the sources capable of complementing the high demand, being a source of clean and sustainable energy. As a result, the treatment of industrial waste aimed at transforming it into clean energy has been quite attractive, since in addition to generating a by-product of great economic value, it also reduces the problem of final disposal. Thus, the present work aims to evaluate the production of H2 from the effluent of the biodiesel industry in a medium containing water under supercritical conditions in a continuous flow reactor, verifying the effect of temperature and feed flow variation on the production of hydrogen and/or synthesis gas generated by the process, performing statistical planning in order to optimize the production of H2 through the Central Composite Design (CCD). The independent variables analyzed were the Feed Flow (Qa) and the Temperature (T) with the temperature varying between 500 and 700 °C and the feed flow between 10 and 25 mL/min. Hydrogen represented the highest percentage among the gases generated in the process, the best condition indicated a percentagem (molar fraction) for H2 of 73.86%, for a temperature of 700°C. Proportionally, the second highest generation gas was CO2, with the highest percentage of 22.39% for a temperature of 529°C. The highest value for gas flow was 5540.80 mL/min (T of 700ºC and Qa of 17.55 mL/min). The response variable studied statistically was the average gas flow (mL/min) compared to the H2 flow (mL/min). The analyses indicated a significant increase in the generation of H2 and gasification of the sample with the increase in temperature, while the feed flow did expressed less influence in relation to the analyzed ranges, but showed a tendency to increase the production of H2 for higher feed flow values. To verify the efficiency of the treatment of the effluent in the supercritical environment, the load of Total Organic Carbon (TOC) and other parameters of the raw effluent were compared with the reduction of these after-treatment. The raw effluent sample that initially had a TOC load of 48250.0 mgC/L, after being subjected to treatment via the supercritical process, showed a greater TOC reduction of 82.62% for test 2, with a Qa of 12. 25 mL/min and temperature of 671°C, in addition to significant reductions in the analyzed parameters, in compliance with national environmental legislation, showing that the process using biodiesel industrial effluent as raw material is efficient for the production of hydrogen and also for its treatment. The use of a homogeneous catalyst based on hydrogen peroxide (H2O2) in order to intensify treatment for removal of TOC showed an improvement in the removal of the organic load of 4.13%.
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    Adsorção de contaminantes emergentes e o ambiente aquático: estrutura fitoplanctônica na presença de sulfametoxazol e diclofenaco
    (Universidade Federal de Goiás, 2022-12-15) Duarte, Joyce Auxiliadora Paiva; Bortolini, Jascieli Carla; http://lattes.cnpq.br/5475113165248615; Ostroski, Indianara Conceição; http://lattes.cnpq.br/9689394915288313; Ostroski, Indianara Conceição; Vendruscolo, Francielo; Nogueira, Ina de Souza
    Chemical products from anthropogenic activities have been one of the main sources of groundwater contamination. They can enter the aquatic environment through domestic sewage, leaching of pesticides and inadequate disposal of chemical products. One of the processes used to remove these contaminants is adsorption, in which different adsorbent materials can be subjected to chemical treatments to improve efficiency in operation. However, environmental analyses are rarely performed with post adsorption effluents. Thus, this study investigates the adsorption process for the emerging contaminants, the anti-inflammatory drug diclofenac (DCF) and the antibiotic sulfamethoxazole (SMX), as well as to evaluate the effects of these drugs on the aquatic environment evaluating the phytoplankton community structure. So, the coconut shell of dendê (Elaies guineenses Jacq) activated carbon was submitted to different chemical treatments and the same were tested in batchs in the removal of DCF and SMX. Kinetic and equilibrium data were obtained for the two contaminants using the best adsorbent. This data was best fitted to Freundlich pseuso-second order models and the best adsorbent was the one treated with phosphoric acid (CDAF), resulting in 80.63% removal for diclofenac and 91.49% removal for sulfamethoxazole. A microcosm experiment was conducted with 16 sampling units, each one with 500 mL of water sample containing phytoplankton exposed to these drugs at different concentrations (0.1, 0.5, and 1.0 mg.L-1). The experiment lasted 15 days, and samples were collected on days 0, 3, 5, 7, and 14 to evaluate the phytoplankton community, the concentrations of the drugs, and the nutrients in the samples. Using the filtered samples from the adsorption assay, representing the effluent from the adsorption process diluted to reach a concentration of 1.0 mg.L-1, plus the acclimated reservoir water containing microalgae, we performe a similar experiment as above, also lasting 15 days. It was identified 6 groups of microalgae, cyanobacteria, diatoms, green algae, myxotrophic flagellates, desmids and xanthophyceans, among them, diatoms and green algae were the most diverse and abundant groups for both experiments. In the first experiment, without containing the effluent, there were significant differences with the use of different concentrations in the samples with DCF in the cyanobacteria groups and significant differences for the desmids group containing SMX. In the post-adsorption effluent experiment, only the desmids group with DCF was significant for the use of the different adsorbents, but by ANOVA the total phytoplankton abundance was significant for the different adsorbents, while in the first experiment the time of duration/exposure to the drugs was significant. In conclusion, this study identified differences in the composition of phytoplankton groups for the two contaminants in the two experiments and in a short period there was a significant response to the interaction between microorganisms and exposure time, and between the different adsorbents used, showing a tendency to decrease the concentration of the drugs in the presence of these microorganisms. Then, the more resistant groups of algae develop more easily, the more sensitive ones decrease or stop developing.
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    Análise termodinâmica da gaseificação do licor negro em água supercrítica
    (Universidade Federal de Goiás, 2022-01-28) Araújo, Beatriz Mendes Mazon de; Souza, Thiago Leandro de; http://lattes.cnpq.br/7431199944070783; Alonso, Christian Gonçalves; Machado, Guilherme Duenhas; Souza, Thiago Leandro de
    Black liquor (BL) is a by-product of the pulp and paper industry process. Its composition is full of organic and inorganic matter and products of lignin’s solubilisation. Nowadays, black liquor has been used as a burning source for the boilers and generates the biggest part of the electricity in the industry where it’s produced. However, the actual process has low efficiency, reduced flexibility, besides promoting the emission of harmful gases and corrosion in boilers. The supercritical water gasification (SCWG) introduces many advantages when compared to current recovery process of black liquor, making possible the generation of high added value gases such as hydrogen and methane and contributing to energetic efficiency of the plants. In this work, a thermodynamic analysis of supercritical water gasification was conducted in a black liquor representative compound, from the Kraft process and eucalyptus wood. The chemical-and-phase equilibrium calculations were performed using Gibbs minimization method, with a non-stoichiometric approach, that is, the direct Gibbs minimization. To simulate the gas phase behaviour, two different models were compared: the ideal gas mixture model and the Peng Robinson state equation with the van der Waals mixing rule. The solid phase was considered as pure graphite carbon. From the simulations performed, a sensitivity analysis of of pressure and temperature influence on the balance composition of the reactive system was conducted, what makes possible to predict behaviors and so, makes easier decision making, saving time and resources. The Results indicate that besides generate value added gases, BLSCWG could also produce more thermal energy when compared to conventional BL recovery process.
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    Otimização dos processos de adsorção e dessorção da octaetilporfirina de níquel em adsorventes à base de carbono
    (Universidade Federal de Goiás, 2021-06-10) Caetano, Gabriela Costa; Ostroski, Indianara Conceição; http://lattes.cnpq.br/9689394915288313; Andrade, Laiane Alves de; Barros, Maria Angélica Simões Dornellas de; Ostroski, Indianara Conceição
    Petroporphyrins are aromatic and nitrogenous macrocycles, of organic origin, which occur naturally in oil and also in sedimentary rocks. In addition to being important biomarker parameters, they have several applications, such as in catalysis and photodynamic therapy. However, they cause damage to the catalytic stages in oil refining. Therefore, due to the importance of removing these compounds from their original fraction, adsorption has been proposed as an alternative process to the commonly used extractive and chromatographic methods. Considering the adsorption and desorption processes of nickel octaethylporphyrin (Ni-OEP), the selection of adsorbents (activated carbon, graphite and partially oxidized graphite) and the optimization of the process operating conditions (solvent, temperature and solid/liquid ratio) were performed. In response, the variables for evaluating the adsorption, adsorption capacity (qe), and desorption, desorption percentage (%desorption) processes were maximized through qualitative and quantitative experimental designs. The kinetics, equilibrium and adsorption thermodynamics studies were carried out; and the adsorbent regeneration cycles were evaluated. As validation of the optimized conditions, qe and %desorption were obtained close to 7.12 mg.g-1 and 37.68%, respectively. As for the adsorption kinetics, the model that best fitted the experimental data was the Elovich equation, in which the equilibrium was reached between 540 and 600 min, with qe = 6.83 mg.g-1; while the equilibrium data were better adjusted by the Freundlich model. The obtained thermodynamic parameters suggest that, under the considered conditions, the adsorption process is spontaneous (ΔG0ads < 0) and exothermic (ΔH0ads < 0). An extraction process was also carried out on the bituminous shales, taken from the Irati Formation, and the presence of nickel octaethylporphyrin was found in the extract. The adsorption and desorption processes of Ni-OEP in the real system had behavior similar to those developed in the model system, with approximately 50% efficiency in petroporphyrin separation. The results obtained allowed to infer that the adsorptive mechanism can be based on the formation of acid-base and π-π interactions between the Ni-OEP molecules and the heterogeneous surface of the coconut shell activated charcoal (CAD), with characteristics of chemical and physical adsorption, respectively.
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    Diagnóstico e avaliação da influência de contaminantes selvagens durante etapas do processo produtivo do etanol
    (Universidade Federal de Goiás, 2021-01-20) Santos, Camila Oliveira dos; Castiglioni, Gabriel Luis; http://lattes.cnpq.br/6050198962131737; Castiglioni, Gabriel Luis; Vendruscolo, Francielo; Rodriguez, Armando Garcia
    Ethanol production represents an important share in the national economy. With the use of sugarcane as a raw material, Brazil is positioned as the second largest producer in the world. Although the ethanol production process is well established, many factors contribute to its efficiency, such as the quality of the raw material, process conditions and microbial contaminants. Sugarcane juice must is a very complex substrate and allows the development of other yeasts of the genus Saccharomyces and non-Saccharomyces, so the microbial population during industrial fermentations can be quite dynamic, and the yeast can be completely replaced in wild yeast process. In view of this, this study proposes to study the fermentative characteristics of contaminating yeast strains isolated from six stages of the production process of an ethanol producing plant in the state of Goiás and the implications that these yeasts could have on the final ethanol yield. The samples were collected from the final melasse, must, concentrated broth, decanted broth, yeast from the vat and fermented wine. From the colonies isolated from the fermented wine, a wild yeast strain with rough appearance and irregular edges was found at a contamination level of 77.4 % of the sample. Thus, fermentative tests were carried out in triplicates with synthetic must of sugar cane with 120 g.L-1 of sugars with a period of 72 hours of fermentation. Firstly, the performance of fermented wine isolated yeast (LFS) was evaluated in comparison with the industrial strains Saccharomyces cerevisiae BG-1, CAT-1, FT-858L and PE-2. LFS obtained lower values in final ethanol concentration, productivity and fermentative efficiency compared to industrial strains. However, in LFS mixed culture fermentative tests at contamination levels of 2, 10, 20 and 30 % with strains BG-1, CAT-1, FT-858L and PE-2, the LFS showed higher levels of final contamination than the initial, thus showing the competence of industrial yeasts over wild yeast, in these same conditions with reuse of the inoculum, the LFS was reduced from 30 % to 0.2 % at the end of 10 consecutive fermentations. In this study, the isolated LFS yeast became more dominant in mixed culture fermentations with the PE-2 strain and in must with calcium oxide additions, between concentrations of 0.05 g.L-1 and 0.30 gL-1 of CaO the results showed a significant drop in fermentation efficiency. The wort of the plant presented an additional calcium concentration of 0.09 g.L-1 after the liming treatment, this concentration is worrying considering that in the tests with the concentration of 0.10 gL-1 of CaO, it was observed that the speed growth rate of LFS was greater than that of the PE-2 strain, possibly this was the condition that favored the critical contamination situation observed in the plant samples, and may mention the possibility of replacing calcium oxide in liming treatment or alternatives that minimize the presence of Ca2+ ions in the must so that it does not favor the development of flocculating yeasts.
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    Investigação da dinâmica de formação de gotas no interior de microcanais via técnicas de CFD
    (Universidade Federal de Goiás, 2020-02-18) Chaves, Igor Lima; Santos, Dyrney Araújo dos; http://lattes.cnpq.br/8987869956010169; Santos, Dyrney Araújo dos; Coltro, Wendell Karlos Tomazelli; Souza, Thiago Leandro de
    Microfluidics has a recent origin and its development is based on microanalytical methods. Defined as the science and technology that addresses the manipulation of small amounts of fluids flowing into channels of tens to hundreds of micrometers, microfluidics today has a diversity of applications due to their characteristics of control efficiency. In this work, the microfluidics applications are briefly addressed, the physical characteristics phenomena that govern it are elucidated by identifying the general flow characteristics, the relevant phenomena and dimensionless studies of flow in channels on the micro-scale, as well as the interfacial properties, which appear in multiphase systems. The mathematical basis used to study the flow phenomena is still addressed. Computational fluid dynamics (CFD) techniques are used as a methodology for development, to overcome the limits of laboratory experimentation (observed here the numerical control of the value for interfacial properties). For the study of multiphase microfluidic flows, the Multiphase Fluid Volume Model (VOF) is used, which allows the flow to be solved numerically and to observe its behavior through the interfaces between immiscible fluids. Given this, in this work, the VOF model was validated with experimental results, both quantitatively and qualitatively, to predict the entire process of generating drops within microchannels. Additionally, the Adaptive Mesh Refining (AMR) technique was used to better track the interface between the fluid phases. The effects of the microchannel geometry, the physical properties of the fluids and the operating conditions, on the size and rate of droplet generation were evaluated using the multiple regression techniques. A dimensionless correlation was also proposed for the prediction of droplet length in which the relative error was 8.2%.
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    Avaliação do uso de carvão ativado na remoção de compostos nitrogenados básicos em diferentes derivados do petróleo
    (Universidade Federal de Goiás, 2020-02-28) Carvalho, Matheus Antoniel Félix de; Ostroski, Indianara Conceição; http://lattes.cnpq.br/9689394915288313; Oliveira, Sérgio Botelho de; Andrade, Laiane Alves de; Ostroski, Indianara Conceição
    In the reserves of heavier oils, high concentrations of nitrogenous compounds found, which, in general, cause problems for the refining process and for the environment. The removal of these compounds through an adsorptive process, later associated with the traditional hydrodesnitrogenation process, is a promising and favorable technique, especially from an economic and operational point of view. In this context, this research sought to study the denitrogenation of oil samples, through an adsorptive process in a batch system, using chemically treated acid activated carbon. Initially, the solution of indoline in toluene was used as a synthetic filler and different activated carbons were evaluated for the ability to remove the compound. From the preliminary test, the use of activated carbon from coconut shell treated with sulfuric acid (CDAS), resulted in the removal of 97.95% of the indoline present in the solution, and was selected for kinetic and equilibrium study. The adsorption kinetics revealed a relatively fast process for the different concentrations studied. The kinetic data were better adjusted to the pseudo-second order model and the balance data were better adjusted to the Freundlich model. Competitive adsorption tests were also carried out between two nitrogenous, quinoline and indoline, with greater removal amounts being observed in solutions with a higher proportion of indoline. Subsequently, the study of adsorption of basic nitrogenous compounds in a crude oil sample was carried out using the central composite planning technique and response surface methodology. The analysis of the main effects showed that the most significant in the adsorption process was the mass of adsorbent. With the optimized variables (54oC, 150 rpm and 1.104g), a removal of 30.77% of basic nitrogenous compounds in oil was obtained. With the optimal conditions, adsorption tests were performed using vacuum residue, diesel S-10 and diesel S-500, in which the removals obtained were 21.56%, 44.44% and 62.09% respectively. Finally, the analysis of mass spectrometry and thermogravimetry proved qualitatively that the adsorption of nitrogen compounds present in the samples occurred.
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    Proposta de uma nova metodologia para a determinação da transição catarateamento-centrifugação utilizando partículas esféricas e não-esféricas em um tambor rotatório via técnicas de CFD
    (Universidade Federal de Goiás, 2020-02-18) Benedito, Wanessa Mendonça; Santos, Dyrney Araújo dos; http://lattes.cnpq.br/8987869956010169; Santos, Dyrney Araújo dos; Souza, Thiago Leandro de; Petri Júnior, Irineu
    Rotary drums are widely utilized in several industrial processes, such as drying, mixing, milling, granulation, among others. The widespread frequent use of rotary drums is due to their simple design and their capability to handle materials characterized by broad size distributions with significant differences in their physical properties. The granular flow inside rotary drums can be classified in different forms: sliding, slumping, rolling, cascading, cataracting, and centrifuging regimes. This classification depends on the drum operating conditions and the physical properties of the particulate material envolved in the granular flow. There are have been no reposts in the literature that presents a precise methodology for cataracting-centrifuging transition identification in rotary drums. This identification is carried out exclusively by visual and subjective way. In this context, the present work aims the proposition of a methodology for the cataracting-centrifuging transition identification, for different particle shapes, using the Multiphase Granular Eulerian Model (MGEM), implemented by CFD simulations. When compared to the Lagrangian model (DEM), the mainly difficult associated with Eulerian model is the particle shape representation, since the solid phase is treated as continuous in CFD simulations. The particle shape for non-spherical particles was indirectly represented in the MGEM using the critical solid fraction (αsc), a parameter associated with the Schaeffer’s frictional model. The present work is also dedicated to overcoming this difficulty. The drum length effect on the cataracting-centrifuging transition was also analyzed. Using the methodology herein proposed was verified that the particle shape and the drum length influence the cataracting-centrifuging transition behavior. For nonspherical particles was required lower values of rotation speed to reach the centrifuging regime condition when compared with spherical particles. It was verified that the lower the drum length, the higher the facility associated with the transition for centrifuging regime for both particle shapes.
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    Utilização de resíduos de grãos de cervejaria na absorção do corante reativo azul 5G em soluções aquosas: sistemas batelada e leito fixo
    (Universidade Federal de Goiás, 2020-02-06) Costa, Fabíola Melazo Amorim Silva; Seolatto, Araceli Aparecida; http://lattes.cnpq.br/1495882445078650; Freitas, Fernanda Ferreira; http://lattes.cnpq.br/0883086742146577; Freitas, Fernanda Ferreira; http://lattes.cnpq.br/0883086742146577; Seolatto, Araceli Aparecida; http://lattes.cnpq.br/1495882445078650; Ostroski, Indianara Conceição; Oliveira, Sérgio Botelho de
    The textile sector is a major consumer of freshwater and its growing development results in the generation of large quantities of potentially toxic waste in watercourses, representing a serious threat to man and the environment. Biological treatment does not always present an effective solution for this type of effluent, leading to the need to use alternative treatment processes. Adsorption is an option that stands out due to its high efficiency and versatility, provided that a viable adsorbent is used for industrial application. This work aimed to study the adsorption of Reactive Blue 5G dye (RB5G), in a batch and fixed-bed system, using brewer spent grains (BSG) as an adsorbent. The adsorbent was characterized by particle size analysis, scanning electron microscopy, infrared spectroscopy, thermogravimetric analysis, and point of zero charge. A rotational central composite design (RCCD) was carried out in the study of batch adsorption and a complete factorial planning for the fixed bed, seeking to find conditions that could favor the dye adsorption process. The characterizations showed that BSG is a heterogeneous material, with an irregular surface and with the presence of pores, in addition to having functional groups on its surface that may be involved in the adsorption process. The adsorption kinetics was obtained, presenting an adsorption equilibrium time of approximately 24 h and a dye removal of 91.5%. Batch adsorption kinetics data were fitted to the pseudo- first-order and pseudo-second-order models, and the pseudo-second-order model was the one that best fitted the experimental data. The result of the statistical design performed for the batch system indicated that the dye adsorption capacity by the BSG was favored when the highest temperature values and lowest values of pH and mean particle diameter (MPD) were used. The adsorption isotherm was obtained under conditions capable of maximizing the result of adsorption capacity, and its data were adjusted to the Langmuir and Freundlich models. The Langmuir model was the one that best adjusted the isotherm data, reaching a maximum adsorption capacity of 83.42 mg g-1 . Considering fixed-bed adsorption, the statistical planning used showed that lower flow rates, associated with higher temperatures and adsorbent masses, resulted in a better performance of the adsorption column. The equilibrium data for the fixed bed were found and presented a good fit for both the Langmuir model and the Freundlich model, which may suggest the coexistence of chemical and physical adsorption. In general, the BSG showed good results for the adsorption of the dye RB5G, thus being an alternative for the removal of this dye.
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    Análise da segregação axial e radial em um leito de jorro cônico
    (Universidade Federal de Goiás, 2020-02-17) Morais, Jéssika Nayara Santos; Santos, Dyrney Araújo dos; http://lattes.cnpq.br/8987869956010169; Duarte, Claudio Roberto; Freitas, Fernanda Ferreira
    The particle cyclic and orderly movement inside a spouted bed has as main advantages of this technique, thus enabling an effective particle-particle and fluid-particle contact, which results in high transfer rates of heat, mass and movement. Due to their intrinsic characteristics, spouted beds have been widely used in industrial processes, however, there are some disadvantages operation inherent, the most complex of which are related to the segregation phenomenon, which occurs due to the multicomponent mixtures use in production lines, causing a non-uniform product formation, which compromises the equipment performance. In this way, a better understanding of the segregation phenomenon inside a spouted bed, is of fundamental importance for its design, operation and optimization. In the present work, a non-intrusive methodology using a solidification-slicing approach was used for the investigation of radial and axial segregation behavior in a spouted bed. The effects of diameter, density, and shape of the particles, as well as the initial particle loading, and the inlet air velocity, on segregation were qualitatively and quantitatively assessed. Regarding the results, binary mixtures with aspect, diameter and density ratios, equals a 2.0, 2.0, and 1.9, respectively, show a random mixture condition. Binary mixtures with diameter ratio of 4.5 and density ratio of 5.8, show radial and axial segregation. As regards to radial segregation, the higher or denser particles, tended to form a central core at the spout region, and the smaller or lighter particles, flowed to the annular region near the spouted bed wall. The particle dynamics seemed not to be significantly affected by changing the particle initial loadings in systems with aspect ratio of 2.0 and density ratio of 5.8, however, affected systems with diameter ratio of 4.5. As expected, the increase in diameter and density ratios caused an increase in radial and axial segregation. The segregation phenomenon for binary mixtures with high density ratio, were shown to be dependent of the initial particle loading configuration, but independent of the superficial gas velocity.
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    Estudo da capacidade de adsorção do carvão ativado de osso bovino para remoção de ácidos naftênicos em mistura modelo e real de querosene de aviação
    (Universidade Federal de Goiás, 2020-02-07) Santos, Débora Federici dos; Ostroski, Indianara Conceição; http://lattes.cnpq.br/9689394915288313; Alonso, Christian Gonçalves; Pereira de Sá, Fernando
    Aviation kerosene is one of the petroleum derivatives obtained by the distillation of crude oil at temperatures ranging from 150 to 300 oC. The presence of naphthenic acids in this fuel provides thermal instability and increased acidity, which consequently increases the corrosion effect on aircraft engines. Naphthenic acid removal can be obtained by adsorption employing porous materials. Thus, the main objective of this work was to evaluate bovine bone activated charcoal (CAB) for its ability to remove n-dodecanoic acid (AD) in model and real mixture of aviation kerosene through data experimental obtained in kinetics and adsorption isotherm. In the kinetic assay, the equilibrium was reached at 180 min for model mixture and 180 min for real mixture, and the theoretical models that best fits the experimental data were pseudo-first and pseudo- second order, respectively. The results indicated a relatively fast adsorption when compared to the use of other adsorbents presented in literature, such as mesoporous sieves and modified perovskites. In the adsorption isotherm, it was found that the amount adsorbed in the equilibrium in model and real mixture was 600 and 780 mg g -1 , respectively. The model with the best fit was that of Freundlich. It was possible to recover the CAB after the adsorptive process by thermal regeneration. Finally, a comparative study was carried out, regarding the efficiency of AD removal, between the CAB and the polymer filtration system used by the fuel distribution company. CAB was the most efficient and could become a viable, inexpensive and regenerative option for use as a filter material.
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    Investigação do processo oxidativo avançado (UV/H2O2/carvão ativado) no tratamento de efluentes industriais: eliminação de fenol
    (Universidade Federal de Goiás, 2017-06-30) Martins, Michelly Freitas de Moraes; Oliveira, Tatianne Ferreira de; http://lattes.cnpq.br/2017895913160804; Castiglioni, Gabriel Luis; http://lattes.cnpq.br/6050198962131737; Castiglioni, Gabriel Luis; Oliveira, Tatianne Ferreira de O; Ostroski, Indianara Conceição; Sá, Fernando Pereira de
    Due to the need for more efficient technologies for the phenol elimination in effluents, the objective of this study was to evaluate the efficiency of the UV/H2O2/AC process and the adsobent behavior in the coupling to eliminate phenol. For a determination of the physical characteristics of the activated carbon, a textural analysis was carried out for isotherms of adsorption and desorption of N2 at 77 K, scanning electron microscopy, thermogravimetric analysis and differential thermal analysis. Regarding the chemical nature of the coal were carried out as techniques of infrared spectroscopy, elemental analysis, Boehm method and zero load point. Adsorption kinetics were used to determine the adsorption capacity, for each of the 11 tests, according to the experimental design 23 + 3 central points, where the pH, temperature and the quantity of carbon activated varied. The experimental data obtained in adsorption kinetics were adjusted to the kinetic models of pseudo-first order, pseudo-second order and intraparticle diffusion, with pseudo-second order being the best represent the adsorption process of all the tests. Adsorption isotherms (15, 30 and 45°C) were then adjusted, adjusting the values to the Langmuir and Freundlich models. All feared a better fit of the data to the Freundlich model. For the treatments H2O2/UV and H2O2/UV/AC a factorial design 22 + 3 central points was used, varying pH and H2O2 concentration and quantified response by rate of phenol removal. For both treatments the pH showed a negative release on elimination rate and a concentration of H2O2 showed positive effect. The best tests for H2O2/UV and H2O2/UV/AC processes were the central points (pH 7 and 20 mmol H2O2), with phenol elimination rates of 89% and 94.16%, respectively. With the presence of a free radical inhibitor (tert-butanol) the kinetic contribution of the hydroxyl radicals was calculated, showing that 77.64% of the phenol elimination in the H2O2/UV/AC treatment was caused by their action. The H2O2/UV/AC coupling process is acceptable, presenting a higher removal rate than the adsorption process with much shorter removal time.
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    Políticas ótimas de alimentação de substrato e enzima em reator de hidrólise operado em batelada alimentada: uma abordagem de controle ótimo com validação automatizada
    (Universidade Federal de Goiás, 2019-08-29) Borges, Alex de Souza; Montaño, Inti Doraci Cavalcanti; http://lattes.cnpq.br/8547423775951223; Suarez, Carlos Alberto Galeano; http://lattes.cnpq.br/5911055089145779; Suarez, Carlos Alberto Galeano; Nucci, Edson Romano; Castiglioni, Gabriel Luis
    The use of fossil fuels contributes to the increase in the amount of free carbon in the atmosphere, because most of the released carbon does not return to the Earth's surface, boosting the global temperature increase. Biofuels are a renewable and environmentally safe alternative, inasmuch as in its production depends that the carbon present in the atmosphere be captured through photosynthesis forming a cycle of production and consumption of carbon. The use of cellulosic leavings is a Muito promising alternative for the production of biofuels as 2G ethanol. The main reason is the fact that these leavings do not enter the competition "food vs fuels " what happens with 1G ethanol. For the consolidation of the industrial production of 2G bioethanol, the economic improvement of the process is necessary. For this reason, there are several researches that seek to make feasible the technique, in this project, a way is presented to improve the feeding of bioreactors, in order to increase the efficiency of cellulose hydrolysis by releasing reducing sugars, which could be converted into second generation alcohol. The use of fed-batch reactors reduces production costs and increases yields, enjoying of rational feed policies of substrates and biocatalysts. Then, this project intends to determine by means of a computational study, the optimized feeding profiles of cellulosic substrate and fed batch enzyme. For this, a semi- mechanistic model is developed, and the optimal control theory for the development of feed profiles is used. For the application of the feed profiles, a system was designed and built, able to automate the feed for both bioreactors and reactors, which alBaixo s to operate with different feeding profiles. The prototype used 3D printing technology to manufacture the mechanical devices, the entire control is done by two microcontrollers in half duplex network, in charge of acting on a helical conveyor. Due to the ability to work with nonlinear systems, the fuzzy nebulous logic was established as the base of the system, being responsible for carrying out the operations necessary to keep the feeder fully operational.
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    Sistemas catalíticos heterogêneos para reações de acoplamento Stille-Migita
    (Universidade Federal de Goiás, 2019-08-27) Godoy, Pedro Henrique Machado; Oliveira, Guilherme Roberto de; http://lattes.cnpq.br/8239498431579015; Alonso, Christian Gonçalves; http://lattes.cnpq.br/7285754665946583; Alonso, Christian Gonçalves; Ostroski, Indianara Conceição; Chagas, Rafael Pavão das
    Carbon-carbon coupling reactions are of fundamental importance in the synthesis of organic compounds. The Stille-Migita reaction is a cross-coupling reaction and occurs when an organotin compound and an organic halide hybridized to sp3 react under the presence of a metal-based catalyst, generally palladium. The reaction has the advantage of being compatible with virtually any functional group and for forming products with complex chains, such as pharmaceuticals and agrochemicals. However, Stille synthesis is usually performed by homogeneous catalysis, which enhances the need for costly purification processes necessary to remove metal debris from the reaction products. Thus, this work synthesized and verified the use of heterogeneous catalysts for Stille coupling reactions, using the efficient and economical method of wet impregnation in its preparation by producing monometallic catalysts with different oxides as support. The catalysts were characterized before and after calcination by thermogravimetry and differential thermal analysis (TG / DTA), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), textural analysis by adsorption/desorption isotherms of N2 and X-ray fluorescence (XRF). The reaction parameters were optimized: time, temperature, type of solvent and catalyst composition. The materials La2O3/Pd and TiO2/Pd showed no catalytic activity, whereas the catalysts Nb2O5/Pd and SiO2/Pd showed good conversions, above 80%. The recycling tests showed considerable loss of activity, which could be associated with filtration and leaching of the active phase between cycles. Nb2O5/Pd showed higher efficiency in the presence of non-toxic solvents (water/ethanol), unusual in Stille reactions. It is expected that this work will contribute to the development of heterogeneous catalysis, particularly in the coupling reactions, since economical methods of synthesis have produced catalytically active materials.
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    Fermentação de licor de hemicelulose advindo do pré-tratamento hidrotérmico do bagaço de malte com as leveduras Scheffersomyces stipitis e Pachysolen tannophilus para produção de etanol 2G
    (Universidade Federal de Goiás, 2019-08-30) Silva, Elizabeth Gonçalves da; Suarez, Carlos Alberto Galeano; http://lattes.cnpq.br/5911055089145779; Montano, Inti Doraci Cavalcanti; http://lattes.cnpq.br/8547423775951223; Montano, Inti Doraci Cavalcanti; Suarez, Carlos Alberto Galeano; Freitas, Fernanda Ferreira; Faria, Fabrícia Paula de
    Ethanol is considered an important alternative energy source that contributes to alleviate energy problems and global warming caused by the accumulation of CO2 from burning fossil fuels. In this sense, the production of ethanol from lignocellulosic materials, known as second generation ethanol (2G), has stood out for presenting environmental advantages and economical. However, the economic viability of this process depends on the utilization of all fermentable fractions present in the different lignocellulosic materials under study, allowing the conversion of both cellulose (C6) and hemicellulose (C5) into ethanol. After the hydrolysis step of these materials is generated as main sugars, glucose and xylose, respectively. Xylose is not fermented by Saccharomyces cerevisiae (yeast widely used in 1G ethanol production), however Scheffersomyces stipitis and Pachysolen tannophilus are considered good biocatalysts for 2G fuel. This work evaluated xylose consumption and metabolites produced in different types of fermentation media. (YPX, MMX and hydrothermal pretreatment liquor from brewer’s spent grain supplemented) in aerobic system and with oxygen limitation. Using two pentose fermenting yeasts, S. stipitis and P. tannophilus, as an industrially viable alternative for the production of bioethanol in brewer’s spent grain hemicellulosic liquor, in order to determine between the two strains cited, a yeast with high ethanol/xylitol selectivity from the fermentation of this liquor through the conversion of xylose. The crops were performed in shaken flasks 500 mL volume filled with 200 mL of inoculated media at 200 rpm with a temperature of 30 ° C; and in 2 mL eppendorfs containing 1.5 mL of the inoculated media at 100 rpm and 30 °C. In cultures with aerobic conditions cell concentrations up to 10.64 g/L were achieved with the P. tannophilus strain in YPX media compared with the cell concentration of 5.42 g/L of the S. stipitis strain in YPX media but in oxygen limitation. At the end of the process were evaluated the kinetic parameters of each yeast in the different culture media and the values for maximum specific speed, xylose conversion factor in cells, xylose conversion factor in ethanol and xylitol were μmax = 0,21 h-1 to S. stipitis in the YPX media under aerobic conditions, Yx/s = 0,56 to P. tannophilus in the YPX media under aerobic conditions, YP/S(etanol) = 0,26 to S. stipitis in the YPX media under oxygen limitation, YP/S(xylitol) = 0,55 to S. stipitis in the MMX media under oxygen limitation. But for the researched environment, hemicellulose liquor from brewer’s spent grain supplemented with MMX components with 1.5 g/L urea obtained better responses for S. stipitis in relation to cell growth and ethanol production under aerobic conditions, already for ethanol production under conditions of oxygen limitation obtained better yield to P. tannophilus, as well as to the production factor of xylitol in the two oxygenation conditions studied. Therefore for better ethanol production the S. stipitis yeast had the highest YP/S(ethanol) = 0,1 under aerobic conditions, and for xylitol production the P. tannophilus strain is the most effective reaching YP/S(xylitol) = 0,46 under conditions of oxygen limitation. With the use of LHBMS media with urea at 6 g/L S. stipitis presented similarity with the conversion factors of urea (1.5 g/L) in the studied oxygen conditions, increasing only the accumulation of ethanol mainly in limitation of oxygen, reaching 3.9 g/L. In this media for P. tannophilus the yield was not plausible, prevailing the media with lower concentration of nitrogen source, because it favored the production of acetic acid, inhibiting the cellular metabolism of this yeast.
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    Influência da adição do octanoato de sódio ao meio do cultivo para a produção de pigmentos por Monascus ruber CCT 3802
    (Universidade Federal de Goiás, 2019-02-28) Martins, Taynara Alvares; Vendruscolo, Francielo; http://lattes.cnpq.br/7105461627589188; Vendruscolo, Francielo; Souza, Adriana Régia Marques de; Freitas, Fernanda Ferreira
    The Monascus ruber fungus can produce at least six important pigments through a metabolic process, where the condensation of one mole of acetate with five moles of malonate in the cytosol leads to the formation of a chromophore hexaceton by polyketide synthase, a multienzyme complex. Medium-chain fatty acids, for example octanoic acid, are synthesized via the fatty acids and bind to the chromophore structure through a trans-etherification reaction, yielding the orange pigment. The reduction of the orange pigment forms the yellow pigment, whereas the amination of orange pigments gives rise to the red pigments. In order to enhance pigment production by Monascus ruber, the present study aimed to study the effect of the addition of sodium octanoate (C₈H₁₅NaO₂) on the growth rate and pigment production by Monascus ruber CCT 3802. Cultures were carried out in solid medium (potato dextrose agar) and liquid supplemented under different concentrations of sodium octanoate, a soluble form of octanoic (caprylic) acid. The pigments produced were subjected to a spectrophotometer and colorimeter scan. The highest radial growth rate was obtained when Monascus ruber was grown in a medium supplemented with 1.5 mM C₈H₁₅NaO₂, 38% higher than the growth rate in the absence of sodium octanoate. In submerged media the addition of 1.0 and 1.5 mM of sodium octanoate were responsible for the production of pigments expressively in only 48 hours of culture. Addition of 3 mM C₈H₁₅NaO₂ caused inhibition of pigment production. Red pigments were observed in the assays with concentrations of sodium octanoate ranging from 0.5 mM to 2.5 mM. The results demonstrated the potential of sodium octanoate as a stimulator of the radial growth of Monascus ruber colonies and the production of pigments.