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Item 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 deBlack 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.Item 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, IrineuRotary 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.Item 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 LuisThe 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.Item 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 ConceiçãoPetroporphyrins 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.Item Estudo da extração e purificação de ficocianina e aloficocianina da biomassa de Arthrospira platensis(Universidade Federal de Goiás, 2018-08-29) Caetano, Renata Klícia Mendes; Ferreira, Fernanda Freitas; http://lattes.cnpq.br/0883086742146577; Castiglioni, Gabriel Luis; http://lattes.cnpq.br/6050198962131737; Castiglioni, Gabriel Luis; Freitas, Fernanda Ferreira; Rodriguez, Armando Garcia; Montano, Inti Doraci CavalcantiThe growing interest in bioactive compounds from renewable natural sources has stimulated more and more studies aimed at increasing the supply of this market. An example is phycobiliproteins, dyes used in various areas, such as food, pharmacological and cosmetic. The microalgae arthrospira platensis (Spirulina platensis) is one of the organisms that stands out most in the production of these dyes, producing allophycocyanin and phycocyanin; these two dyes are the ones that today have more demand in the market. These proteins have their application determined from their degree of purity obtained with the absorbance ratio read at 620 nm of the extract used for the absorbance read at 280 nm. For use of these dyes, in the food area, a purity value greater than 0.7 should be obtained, and for use in the analytical area, the purity should be greater than 4.0. In view of the importance of these dyes and their degree of purity, in order to develop means of obtaining phycobiliproteins in a purity satisfactory for use in food industries, phase separation techniques were used in aqueous biphasic systems (ABS) to evaluate the action of pH, phosphate salt concentration and the concentration of low chlorine content cationic polymer and polyethylene glycol 4000 (PEG 4000) on the efficiency of the extraction and purification process of Spirulina crude extract and also in the pre-purified extract of phycocyanin obtained by centrifugation. For this, a first experiment was carried out using a factorial design 2 4 to evaluate the variables that most influenced the extraction and purification of phycocyanin, allophycocyanin and purity of the extract. Values of 2.6 mg.mL -1 were reached for phycocyanin concentration, 1.4 mg.mL -1 for the allophycocyanin concentration and 1.6 for the purity of the extract. The significance of the PEG 4000 and PBC polymers was observed for extraction and purification of phycobiliproteins. Then, a second design was carried out, a Rotational Central Composite Design (RCCD) 2 2 , fixing the phosphate salt, pH and varying the PEG and low chlorine content cationic polymer concentrations. At the end of the extraction, it was possible to find concentrations of 2.7 mg.mL -1 for Phycocyanin, 1.3 mg.mL -1 of allophycocyanin and 2.5 for the purity of the extract, evidencing that the techniques used are effective for the extraction process and purification of phycobiliproteins, in which the levels achieved allow their use and application in food industry.Item 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 ConceiçãoIn 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.Item 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 deMicrofluidics 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%.Item 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 deThe 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.Item Otimização numérica da produção de glutationa por saccharomyces cerevisiae utilizando subprodutos industriais(Universidade Federal de Goiás, 2016-05-02) Cruz, Késia de Souza; Geraldine, Robson Maia; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4792431Y6; Castiglioni, Gabriel Luis; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4778449D6; Castiglioni, Gabriel Luis; Geraldine, Robson Maia; Freitas, Fernanda Ferreira; Putti, Fernando FerrariRecent studies show that often, pathologies are caused by Reactive oxygen species (ROS). The ROS are associated with the oxidative stress in the cells. The body uses the antioxidants to defend itself from the consequences of this process. An example of an antioxidant with different functions in an organism is the Glutathione (GSH). It is a cellular thiol with low molecular mass, that’s synthesized by chemical, enzymatic and fermentative methods. Since it is environmentally and economically viable, the use of the fermentative process has gained scientific visibility. The use of mathematical models is an alternative that helps in the production of Glutathione. Considering these observations, the present study's aimed to elaborate a mathematical model for production and prediction of GSH for Saccharomyces cerevisiae, as well as to validate its numerical optimization experimentally. For the mathematical model in this process, was used the Central Composite Rotational Design 2², having as an answer, the GSH and biomass values in function with the concentration of molasses and glycerol during a period of 96 hours of fermentation. Based on these results, a hybrid model was made, having as a result, the specific rate of GSH formation. The final model was adjusted to a polynomial function using the method of least squares. Experimentally, the maximum production of GSH was found to be, in 72 hours (119,6 mg L-1) using 76,9 g L-1of molasses and glycerol, respectively. Applying the model for similar conditions, it was estimated to a 118,6mg L-1. The experimental results were then statistically analyzed to verify their similarity. The numerical optimization was made by setting the clock for 72 hours. At this step, the concentration of molasses and glycerol were varied until the best conditions to produce GSH were met. The optimization helped to derive an estimate that 70 g L-1of sugar cane molasses and 40 g L-1of glycerol can guarantee the production of 126 mg L-1of GSH. Based on the accuracy of the observations, the same conditions were used as a central point for the validation of the model - Factorial Design2². The results obtained under these conditions helped establish that the central point of the proposed design for the validation of the model, is 127,3mg L-1of GSH in 72 hours. The validation of this mathematical model by the numerical optimization proved that it was effective for the production and prediction of Glutathione by Saccharomyces cerevisiae, using industrial by-products.Item Simulação de uma unidade piloto de destilação de água empregando energia solar(Universidade Federal de Goiás, 2016-12-21) Damasceno, Camila Teles; Noda Pérez, Caridad; http://lattes.cnpq.br/8518548259609686; Noda Pérez, Caridad; Costa, Orlene Silva da; Oliveira, Sérgio Botelho deThis work proposes the use of a distiller that uses solar energy for the production of distilled water suitable for use in chemical analysis laboratories of the Federal University of Goiás (UFG).The choice of solar distiller is due to the high incidence of solar radiation in Brazil, and because this type of equipment does not consume electricity, does not generate wasted drinking water, is easy to operate and requires low technology.A study was carried out on the intensity of radiation incident in the dry winter and wet summer period of the municipalities of Catalão, Goiânia and Jataí, where the campus of this university is located, based on the Duffie and Beckman model (2013).From the generated radiation data it was possible to determine what 20º would be the best angle for the equipment coverage, so the pilot model was built and installed at the Chemistry Institute of UFG in the city of Goiânia.With the experimental data of water temperature (Tw) and the distiller cover (Tg) recorded every hour (from 8 a.m. to 6 p.m.), the distiller's energy balance, based on the Dunkle model ( 1961), by which it was calculated the heat transfer coefficients by convection (hcw) and evaporation (hew), convective heat transfer rates (qcw) and evaporation (qew), mass transfer rate ( ew) and the efficiency of the distiller (ηi).The results obtained allowed to conclude that the coefficient of heat transfer by evaporation and its corresponding rate were higher than the coefficient of heat transfer per convection and its respective rate.The production of distilled water in winter and summer was 0.31 and kgm-2dia-1, respectively, and the distiller's maximum efficiency was 5.4% in winter and 41.33% in summer. The obtained water meets the parameters of the Brazilian Pharmacopoeia and can be used in chemical laboratories in substitution to that obtained in the electric distillers.Item 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 SouzaChemical 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.Item Adsorção de compostos nitrogenados utilizando carvão ativado(Universidade Federal de Goiás, 2017-06-22) Ferreira, Maria Eugênia de Oliveira; Alonso, Christian Gonçalves; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4777466U2; Ostroski, Indianara Conceição; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4751610A4; Oliveira, Sérgio Botelho de; Vaz, Boniek Gontijo; Alonso, Christian GonçalvesHeavy petroleum fractions, especially the vacuum residue, concentrate the largest amounts of nitrogen compounds. Such compounds are considered contaminants of the refining process, and interfere in the conversion steps to obtain lighter derivatives from the heavy fractions. In this study, the aim was to evaluate the removal of nitrogen compounds by adsorption process. Quinoline solution solubilized in toluene was used as a synthetic filler. Commercial activated carbons from coconut shell of babaçu and dendê in their original form and chemically modified with concentrated solutions of nitric and sulfuric acid, as well as sulfonated carbon developed from the rice husk, were evaluated for the adsorption capacity against compounds nitrogen residues present in the vacuum residue and synthetic charge. The textural characteristics of the adsorbents were also evaluated, in which it was observed that the modification with acid reduces the specific area of the activated carbons, but it promotes an increase in the removal of quinoline from the medium. From the preliminary batch adsorption test, the activated carbon from dendê treated with sulfuric acid (CDAS) was able to remove 67.08% of the quinoline present in the solution and was selected for kinetic and equilibrium study. The adsorption kinetics of quinoline were relatively fast for the three concentrations studied (500, 2000, 5000 mg L-1), reaching equilibrium after 240, 120 and 60 minutes of contact, respectively. The kinetic data for the three systems fit the pseudo-second order model better. The equilibrium data were better adjusted to the Freundlich model, revealing the physisorption character of adsorptive process. The maximum adsorption capacity obtained by Langmuir model was 56.63 mg g-1. The results show that CDAS is a promising adsorbent for the removal of quinoline in organic medium. In relation to the vacuum residue sample, batch adsorption tests were conducted in such a way to ascertain the efficiency in class N removal. The results of Mass Spectrometry, ESI (±) Orbitrap MS, showed that the adsorbents CBB and CBAN were more selective in the removal of the non-basic nitrogen compounds, while the basic nitrogenous ones were more persistent and were not removed by any of the adsorbents tested.Item 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 dasCarbon-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.Item Estudo da eficiência do pré-tratamento do bagaço de abacaxi com perôxido de hidrogênio alcalino em diferentes granulometrias na obtenção de açúcares redutores totais(Universidade Federal de Goiás, 2016-04-18) Macedo, Lorena Costa Vasconcelos; Freitas, Fernanda Ferreira; http://lattes.cnpq.br/0883086742146577; Seolatto, Araceli Aparecida; http://lattes.cnpq.br/1495882445078650; Seolatto, Araceli Aparecida; Freitas, Fernanda Ferreira; Rosa, Paula Rúbia Ferreira; Caliari, MárcioThis study examined the performance of pineapple bagasse for the production of reducing sugars after pretreatment with alkaline hydrogen peroxide and acid and enzymatic hydrolysis. They were determined after conducting preliminary acid and enzymatic hydrolysis the best conditions for the bagasse pineapple used in dry form, "in natura" and washed. Chosen the dry pomace condition, this was separated granulometrically, wherein the average diameter fractions of 1.242 mm and 0.564 mm were predominant among the amounts of sieved bagasse, these two fractions were then chosen and denominated 20 and 48 mesh respectively, to evaluate the influence of particle size on the release of total reducing sugars. Type DCCR designs were conducted to evaluate the influence of weather pretreatment (h) Temperature (°C) and concentration of alkaline hydrogen peroxide (%) in the performance of acid and enzymatic hydrolysis, which was measured by the release of total reducing sugars (TRS). Moreover, the mass loss caused in the samples 20 and 48 mesh after pretreatment with alkaline hydrogen peroxide were observed. The results showed that the highest yields of reducing sugars obtained for fractions 20 and 48 mesh, both the acid hydrolysis with diluted sulfuric acid 2.9% (v/v) as the enzymatic hydrolysis with 9 FPU / g dry biomass at 50 °C and pH 4.8, were obtained when using lower levels of time, temperature and concentration of peroxide to the pre-treatment with hydrogen peroxide. The ART mass analysis after 8 h of reaction at 20 °C and concentration of alkaline hydrogen peroxide at 2% (v/v) to acid and enzymatic hydrolysis at residue 20 mesh, were 0.092 g/g ART dry bagasse and 0.063 g/g of dry bagasse ART respectively. As for the enzymatic and acid hydrolysis in the residue 48 mesh under the same conditions was 0.074 g/g dry bagasse ART and 0.058 g/g ART respectively. Therefore, it is believed that the smaller mass loss is related to obtaining higher yield of reducing sugars. This is because, observing the mass losses of such biomasses intended to acid and enzymatic hydrolysis, in both fractions pineapple pulp, 20 and 48 mesh after pretreatment with alkaline hydrogen peroxide were detected smaller mass loss of 77.829% and 83.182% for bagasse of 20 mesh and 83.724% and 83.493% for the bagasse of 48 mesh.Item Pré-tratamento hidrotérmico do bagaço de malte (BSG) visando a produção de etanol de segunda geração(Universidade Federal de Goiás, 2019-02-26) Maione, Nicole Ribeiro; Rodrigues, Dasciana de Sousa; http://lattes.cnpq.br/8321796631800718; Montano, Inti Doraci Cavalcanti; http://lattes.cnpq.br/8547423775951223; Montano, Inti Doraci Cavalcanti; Rodrigues, Dasciana de Sousa; Freitas, Fernanda Ferreira; Delabona, Priscila da SilvaBrazil is the third largest producer of beer in the world and brewer’s spent grain (BSG) is the main residue of this industry. As a low-cost, available lignocellulosic material, it has become an attractive alternative for the production of biofuels and other chemicals. Thus, to be able to take advantage of BSG as a raw material it must first be pre-treated. Hydrothermal pre- treatment allows the removal of the fraction of hemicellulose present in the lignocellulosic material and brake the lignocellular crystallinity. In this work, initially was performed the characterization of the BSG in natura, obtaining 25.1% of cellulose, 20.9% of hemicellulose, 20.3% of lignin and 28.0% of proteins. Evaluating the effect of temperature and time of hydrothermal pretreatment, the best result was at 160°C and 60 min, with cellulose yield of 64.8% and removal of hemicellulose of 62.0%. In a second experiment, the temperature and solids content of the pretreatment and its effect on the enzymatic hydrolysis were analyzed, obtained better glucose yield, 74.1%, in the enzymatic hydrolysis of the pretreated at 180°C and 40 g of dry BSG, containing 0.020 g furfural, 0.062 g HMF and 0.902 g acetic acid (per 100 g dry BSG) which are inhibitors of the fermentation process. As the present study aimed at the production of 2G ethanol by fermentation, the condition of pretreatment 160 °C, 80 g was chosen for the pretreatment kinetic study, since it presented a high glucose yield, 66.3%, and a lower concentration of inhibitors of the fermentation process with 0.020 g Furfural 0.020 g HMF and 0.444 g acetic acid (per 100 g dry BSG). In a second condition, pretreatment kinetics were performed for comparison reasons (200°C / 80g). Samples were withdrawn at times 0, 5, 10, 20, 40 and 60 min. Results showed that the reaction time of 10 min obtained better cellulose yield in the solid fraction at 160°C and at 200°C the highest yield of cellulose was in 5 min. In the liquid fraction, the concentrations of oligomers did not change significantly when varied the reaction time at 160°C, while in the temperature of 200°C there was a considerable increase of oligomers in 5 minutes. The amounts of glucose released in the processes studied were not satisfactory high to consider hydrothermal pretreatment to BSG as feasible for the production of second generation ethanol.Item 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 deDue 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.Item 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 FerreiraThe 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.Item Síntese de nanopartículas de óxido de ferro funcionalizadas para remoção de Pb2+(Universidade Federal de Goiás, 2016-05-30) Matos, Hannah Larissa Siqueira; Lima, Emília Celma de Oliveira; http://lattes.cnpq.br/0176904550618260; Ostroski, Indianara Conceição; http://lattes.cnpq.br/9689394915288313; Ostroski, Indianara Conceição; Lima, Emília Celam de Oliveira; Martins, Paulo Roberto; Barros, Maria Angélica Simóes Dornellas deLead is a heavy metal that can be found in wastewaters of acid battery production, pigment and dye factories, petrochemical and automobile industries. It can cause serious damages to environment and human health even at trace level due to its bioaccumulation capacity. Numerous techniques are used for removal of heavy metals in wastewaters, the adsorption has been a technique of high efficiency and low cost with the use of alternative adsorbents, like nanoparticles. Iron oxide nanoparticles have low toxicity, they are biocompatible, and due to their small size, they have a huge surface area and high reactivity. In this study, colloidal suspensions of functionalized iron oxide nanoparticles with citrate were prepared using a modified coprecipitation methodology of Fe3+ and Fe2+ ions in basic medium. With the purpose of simplifying the synthesis to possible uses of nanoparticles in large scale, the colloidal suspension was obtained in one step and subsequent steps in the synthesis, such as washing and drying, were dismissed. Moreover, this synthesis does not generate waste, it has low cost, and simple application. The nanoparticles were characterized by X-ray diffraction, infrared spectroscopy, transmission electron microscopy, point of zero charge, and molar ratio [Fe3+]/[Fe2+]. Colloidal suspensions were used for removal of Pb2+ in synthetic solutions. For this, studies were conducted to evaluate the influence of synthesis modifications in removal of metal ions, the pH and metal concentration effect, as well as the mechanisms of adsorption, kinetic and thermodynamics parameters. VIII It was observed that besides the adsorption process, nanoparticles were coagulated and precipitated, up tp 97% of Pb2+ removal in was obtained in high metal concentration. Thus, due to coagulation another step of separation was not necessary, which could be costly in wastewater treatment.Item Catalisadores a base de Cu, Ni e Mg suportados em Al2O3 aplicados à gaseificação de etanol em meio contendo água em condições supercríticas(Universidade Federal de Goiás, 2018-09-28) Melo, Jarbas Almeida de; Souza, Thiago Leandro de; http://lattes.cnpq.br/7431199944070783; Alonso, Christian Gonçalves; http://lattes.cnpq.br/7285754665946583; Alonso, Christian Gonçalves; Souza, Thiago Leandro de; Santos, Dyrney Araújo dos; Queiroz Júnior, Luiz Henrique KengIn this work the synthesis of catalysts was carried out with the objective of H2 production from gasification of ethanol in medium containing water under supercritical conditions. Based on reports from the literature, Cu, Ni and Mg were selected as components for the active phase, alumina (Al2O3) as catalysts support. The catalysts were prepared from aqueous solutions of nitrate salts precursors of Cu, Ni and Mg. The catalysts were characterized by X-ray fluorescence (FRX), scanning electron microscopy, thermogravimetric and thermal differential analysis (TG/ATD), X-ray diffraction (DRX) and textural analysis by N2 adsorption / desorption isotherms at -196 ° C. The TG/ATD analysis indicated that the calcination of the catalytic precursors was sufficient for the removal of water and decomposition of the nitrates of the metal salts precursors of the active phase. In the FRX analysis, the increase in the concentration of the metals in relation to the nominal values after the synthesis of the catalysts was characterized, with an increase of 20 to 40% depending on the metal due to the loss of water from the alumina support. The FRX analysis of the catalysts used in the catalytic tests shows that there was no significant leaching during the gasification process. DRX analysis have characteristic results that the metals are in amorphous form or dispersed in the form of small crystallites. Textural analysis of N2 adsorption / desorption isotherms indicated a reduction of approximately 60% in the specific surface area between the alumina and the calcined alumina and the specific area values between the alumina and the metal catalysts were kept close. The catalytic tests were performed at a pressure of 25 MPa and at temperatures of 400 to 650 ° C. A 10/1 molar water / ethanol solution was fed. In the catalytic tests H2, CH4, CO, CO2, C2H4, C2H6, C2H4O were obtained. The highest ethanol conversions were obtained at the temperature of 650 ° C for the catalysts NiO/Al2O3 and NiO-MgO/Al2O3, both 81%. The highest yield was 0.41 mol H2 / mol ethanol fed to the NiO / Al2O3 catalyst, at a temperature of 600 ° C. The highest selectivity at the temperature of 600 ° C was 39%, obtained by the NiO/Al2O3 catalyst.Item 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 FerreiraThe 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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