Mestrado em Engenharia Química (IQ)
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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 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 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 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 MachadoGlyphosate 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.Item 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 AndreuFor 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.Item 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 GarciaEthanol 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.Item 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 JúlioThe 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.Item 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 deThe 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%.Item 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 LúcioIn 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.