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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 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 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.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 Análise termodinâmica da reforma com vapor de água de um composto modelo de bio-óleo para produção de hidrogênio(Universidade Federal de Goiás, 2018-09-28) Trevisan, Ivo Junior; Alonso, Cristian Gonçalves; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?metodo=apresentar&id=K4777466U2; Souza, Thiago Leandro de; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?metodo=apresentar&id=K4250090T1; Souza, Thiago Leandro de; Alonso , Cristian Gonçalves; Cardozo Filho, Lucio; Oliveira, Sérgio Botelho de; Ostroski , Índianara ConceiçãoIn this work, a thermodynamic analysis of the water vapor reforming reaction of a bio-oil model compound was performed and the objective is producing hydrogen through an alternative source of fossil fuels. The bio-oil model compound was considered to be a molar fraction of 1:1:1 mixture of phenol, acetic acid and hydroxyketone and the thermodynamic data were obtained in DIPPR® software version 1.2.0. The chemical and phase equilibrium were calculated by the Gibbs energy minimization method. Constant pressure of 1 bar, temperature ratio from 673.15K to 1273.15K and water and carbon ratio of the substrate (H2O(v)/C(ent)) of 0.01 to 3.00 were used to construct the optimization problem and the software GAMS® version 2.0.29.8 was used by optimization problem resolution. The gas phase was considered with behavior of ideal gas and the solid phase was considered with solid carbon. Hydrogen, water, carbon monoxide, carbon dioxide, solid carbon and methane formation data were collected after solving the optimization problem and the reaction heat and syngas production were also analyzed. The maximum hydrogen yield obtained was 1.3 moles in the 1100 K region with 1 mole water per carbon of the substrate (H2O(v)/C(ent)). It was also observed that the greater amount of syngas occurs in the 950 K region and 1,2 of the H2O(v)/C(ent) ratio. An exothermic region and an exothermic region were observed in the reaction heat analysis and in the exothermic region there is a higher incidence of coke and methane generation and in the endothermic region a higher incidence of hydrogen and carbon monoxide generation.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.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 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 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 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 Catalisadores heterogêneos aplicados à reação de Biginelli(Universidade Federal de Goiás, 2017-03-07) Nascimento, Letícia Gomes do; Oliveira, Guilherme Roberto de; http://lattes.cnpq.br/8239498431579015; Alonso, Christian Gonçalves; http://lattes.cnpq.br/7285754665946583; Alonso, Christian Gonçalves; http://lattes.cnpq.br/7285754665946583; Oliveira, Guilherme Roberto de; http://lattes.cnpq.br/8239498431579015; Andrade, Fabiano Molinos de; Arroyo, Pedro AugustoThe Biginelli reaction involves the cyclocondensation of three reagents in the presence of an acid catalyst to obtain dihydropyrimidinones (DHPMs).This compound and its analogues are widely known to possess various pharmacological properties, such as antibacterial, antiinflammatory, antifungal, antiviral, anticancer and antihypertensive. This reaction is usually carried out via homogeneous catalysis, which presents, however, some difficulties, such as regeneration of the catalyst and difficult separation of the final product, thus becoming an obstacle for industrial use. In the present work, it was proposed the use of two classes of heterogeneous catalysts, which are: metal oxides and acid carbons in order to achieve attractive characteristics in the Biginelli reaction, as a reduction of reaction time and increase in yield. The acidic carbons were prepared by carbonization by impregnation of agroindustrial residues with sulfuric acid at a temperature of 200 °C in the mass ratio of 1:10 (precursor: H2SO4) for 6 h. The pure HY-340 and Nb2O5 were both tested and chemically treated with a solution of 30% sulfuric acid. The catalysts were characterized by X-ray diffraction (XRD), infrared spectroscopy (FTIR), thermogravimetric (TG), differential thermal analysis (DTA), textural adsorption/desorption analysis of N2 at -196 °C and desorption of ammonia at programmed temperature (DTP-NH3), scanning electron microscopy (SEM) and X-ray Dispersive Energy Spectrometry (EDS). The contents of C, N, O and S present on the surface of the coals were quantified by Elementary Analysis (CHNS-O). Exploratory catalytic tests were carried out to define the best experimental conditions of solvent, temperature, molar ratio and amount of catalyst. The results obtained allowed to establish the best experimental conditions for the realization of the Biginelli reaction. Thus, the following parameters were adopted to evaluate the performance of the different catalysts. These are: 5% catalyst content (by mass), molar ratio of 1 Benzaldehyde: 1,5 Methyl acetoacetate: 1,5 Urea, without solvent and temperature of 130 °C. The best catalyst was Nb2O5 treated with sulfuric acid, whereby a yield of 94% of dihydropyrimidinones (DHPMs).Item Catalisadores heterogêneos para produção de chalconas: reação de condensação de Claisen-Schmidt(Universidade Federal de Goiás, 2016-03-07) Winter, Caroline; Pérez, Caridad Noda; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4792149E3; Alonso, Christian Gonçalves; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4777466U2; Alonso, Christian Gonçalves; Pérez, Caridad Noda; Machado, Nádia Regina Camargo Fernandes; Oliveira, Guilherme Roberto deThe members of flavonoids and chalcones family have attracted great interest because of their pharmacological applications as antibacterial, anti-inflammatory and anticarcinogenicagents, and are commonly synthesized by Claisen-Schmidt condensation between acetophenone and benzaldehyde derivatives. This reaction is usually catalyzed under homogeneous conditions which present, however, several drawbacks such as catalyst recovery and waste disposal problems. This work proposes the use of a variety of heterogeneous catalysts to achieve good results for condensation Claisen-Schmidt reaction in terms of conversion and chalcones selectivity, when compared to the homogeneous catalysis. Two groups of catalysts were tested: metal oxides and activated carbons. Magnesium oxide catalysts were prepared by hydrothermal treatment and magnesium, niobium, lanthanum and titanium oxides by rehydration of commercial precursors, all methods followed and not followed by cesium impregnation. The activated carbons used as catalysts were Babassu, Bahia Coconut, ox bone and Dendê, raw and treated with sodium hydroxide. The catalysts were characterized by scanning and transmission electron microscopy, thermogravimetric analysis, differential thermal analysis, determination of the specific superficial area by the adsorption/desorption of N2 at 77 K method, infrared spectroscopy, X-ray diffraction and temperature-programmed desorption of CO2 and NH3. The basic sites of carbons were quantified by Boehm Method. Finally, the performance of the catalysts was evaluated on the Claisen-Schmidt reaction between Acetophenone and 4-nitrobenzaldehyde, and the conversion was quantified by high performance liquid chromatography. The best catalyst was treated babassu activated carbon, whose conversion achieved was 92,38%.Item Desenvolvimento e avaliação de sistemas catalíticos heterogêneos para reações de acoplamento carbono-carbono de Suzuki-Miyaura(Universidade Federal de Goiás, 2019-02-21) Souza, Guilherme Botelho Meireles de; Oliveira, Guilherme Roberto de; http://lattes.cnpq.br/8239498431579015; Alonso, Christian Gonçalves; http://lattes.cnpq.br/7285754665946583; Alonso, Christian Gonçalves; Oliveira, Guilherme Roberto de; Ostroski, Indianara Conceição; Chagas, Rafael Pavão das; Matos, Ricardo Alexandre Figueiredo deSuzuki-Miyaura cross-coupling reactions are one of the most efficient and powerful tools for the formation of new carbon-carbon bonds, which have been widely applied in modern organic synthesis and industrial processes. Generally, these reactions are carried out by homogeneous catalysis, employing expensive palladium complexes such as PdCl2 associated with harmful phosphine ligands. However, these synthetic route presents several drawbacks such as high associated toxicity, catalyst recovery difficulties and waste disposal problems. In this context, several heterogeneous catalysts were proposed to overcome the great challenge of separation and recovery of homogenous catalysts. Also, a low-cost catalyst was presented as an alternative for the usage of palladium as the main Suzuki-Miyaura cross-coupling catalyst. Palladium, Nickel, Copper and Cobalt catalysts supported on niobium pentoxide (Nb2O5) were synthesized via wet impregnation method and tested for the Suzuki-Miyaura coupling reaction between phenylboronic acid and 4- bromoanisole. The catalysts were well characterized by scanning electron microscopy, N2 physisorption, X-ray diffraction, X-ray fluorescence, Thermogravimetry/Differential Thermal Analysis. Both Copper and Cobalt catalyst did not show any activity towards Suzuki- Miyaura cross-coupling reaction. Palladium catalyst resulted in high isolated yields (up to 91%) under optimized conditions. Satisfactory yields (up to 48%) were achieved employing the Nickel catalyst. Recycling tests were performed and significant loss in activity was observed after the first catalytic cycle, which can be attributed to catalyst loss during its retrieval by filtration between cycles, leaching of the active phase, in particular for Pd/Nb2O5 catalyst, or the poisoning by inorganic species (mostly potassium) on the spent catalyst’s surface.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 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, FernandoAviation 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.Item Estudo da competência de Saccharomy cescerevisiae em co-cultura para a produção de etanol(Universidade Federal de Goiás, 2017-02-24) Santos, Mayara Vieira; Souza, Adriana Régia Marques; http://lattes.cnpq.br/3723989528702465; Castiglioni, Gabriel Luis; http://lattes.cnpq.br/6050198962131737; Castiglioni, Gabriel Luis; Oliveira, Bruno Motta; Freitas, Fernanda FerreiraUsually the inoculum used during the beginning of the harvest of ethanol production is constituted by the combination of two or more yeasts strains and in the end the most adapted one will predominate, either inoculated yeast or indigenous wild yeast. The proportion used in these industries are established empirically, of which little is known about the kinetic parameters and the influence that each yeast has on the production of ethanol and on the other metabolites. An experimental design from the blending design with Saccharomyces cerevisiae ATCC7754, S. cerevisiae CAT-1, S. cerevisiae PEDRA-2, S. cerevisiae MONASTRELL strains was proposed to understand how the interaction among the different blends occurs comparing with the ethanol, biomass, acetic acid, glycerol and biomass consumption. This study showed that the inherent characteristics to each yeast can influence the behavior of the kinetics parameters of the culture with two yeasts. It was verified that the combination among three yeasts presented similar metabolic behavior. From the blending design it was possible to elaborate mathematical models that predicts the ethanol, biomass, glycerol, acetic acid and residual sucrose amount in all four yeasts mixtures. It was also possible to identify that the mixture of CAT-1 and PEDRA-2 presented higher ethanol production when cultivated in a 1: 1 ratio, and also in the cultivation with the two yeasts (CAT-1 and PEDRA-2) to CAT-1 was higher in yeast. This research also presents the synthetic cane juice composition and the detail of growth kinetics, substrates consume and production of MONASTRELL yeast products that had not been studied until now.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 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 Estudo da obtenção de açúcares redutores totais a partir do bagaço de laranja (Citrus sinenses) por hidrólises ácida diluída e enzimática(Universidade Federal de Goiás, 2016-04-18) Nogueira, Danielle Pires; 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; Suarez, Carlos Alberto GaleanoDue to the recent research for new fuels from renewable sources ethanol has been gaining momentum, because it can be produced from diverse raw materials, such as agro-industrial residues. The objective with this work was to study the production of reducing sugar by dilute acid, and enzymatic hydrolysis of the orange bagasse from juice industry. The orange bagasse was collected, cut into pieces, and crushed. Granulometry, and the contents of moisture, ashes, holocellulose, cellulose, hemicelulose, soluble and insoluble lignin were determined. The pre-treatment was done with calcium hydroxide following what was previously tested by Silva et al. (2013). A pre-test of the enzymes combination was done using 2 g of pre-treated biomass, in dry base, using 3 FPU/mL of cellulase, and 0 U/g and 3 U/g of xylanase. For the hydrolysis two central composite factorial 2³ designs were done, with the answer in total reducing sugars (ART). For the dilute acid hydrolysis the factors were HCl concentration, temperature, and time, and for the enzymatic the concentrations of cellulase and xylanase and time. The granulometry showed that 47.75% of the biomass with diameter over 0.833 mm, 32.84% of the biomass with an average diameter of 0.564 mm, and 19.41% of the biomass with diameter under 0.295 mm. The moisture content prior to drying was 84.69% and 7.38%, the ashes content was 3.79%. The cellulose content was 22.90% and the hemicellulose was 3.39%. The lignin content was 9.90%. The reducing sugar results for the acid hydrolysis varied from 9.32±0.68 mg ART per g of biomass to 30.15±0.31 mg ART per g biomass, the most significant factor was temperature, and the least was time. It was not possible to find the optimum region with the studied factors. The reducing sugar results for the enzymatic hydrolysis varied from 75.33±3.82 mg ART per g biomass to 99.66±0.62 mg ART per g biomass, the most significant factor was the cellulase concentration, and the least significant the xylanase concentration. The studied factors did not show the optimum region to maximize the reducing sugars content. The enzymatic hydrolysis produced larger concentrations of reducing sugars than the acid hydrolysis.Item O estudo de adsorção dos corantes azul royal tiafix e preto tiassolan utilizando o carvão de osso como adsorvente(Universidade Federal de Goiás, 2016-07-08) Moura, Rowander Alexandre; Freitas, Fernanda Ferreira; http://lattes.cnpq.br/0883086742146577; Seolatto, Araceli Aparecida; http://lattes.cnpq.br/1495882445078650; Ostroski, Indianara Conceição; Oliveira, Sergio Botelho de; Freitas, Fernanda FerreiraThis project aimed to carry out the study of adsorption of dyes called AR.TF and P.TS using bone char as an adsorbent. To determine the physical characteristics of char were used the particle size analysis techniques, adsorption and desorption of N2 at 77K, scanning electron microscopy and X – ray diffraction. Regarding the coal chemical nature was employed the techniques infrared spectroscopic and point of zero charge (PZC). It was conducted adsorption kinetics for the determination of the adsorption equilibrium time, being achieved in approximately 1 hour and 30 minutes to the AR.TF dye and 4 hours and 50 minutes to the P.TS dye. The experimental data obtained in the adsorption kinetics were fitted to the kinetic model pseudo first order pseudo second order and intra particle diffusion model having been pseudo second order best represented the adsorption of both dyes. It was used a 23 factorial design of the central composite type, being the variables agitation, temperature and pH and quantified response the adsorption capacity (q). With this, it became possible to analyze the influence of factors as well as the interactions between them, collaborating with obtaining the influence of the independent variables on the response study. Finally, it was performed the experiments at different temperatures for constructing the adsorption isotherms, by adjusting the values at the Langmüir and Freundlich models. For dyes AR.TF and P.TS had to be a better adequacy of the data to the Freundlich model, but it is important to note that some data are also adjusted well to the Langmuir model. Through this fact makes it possible to hypothesize the coexistence of two adsorption kinds at the adsorption process of dyes of this project. Generally the bone char showed acceptable as adsorbent for the adsorption of AR.TF and P.TS dyes having a higher removal efficiency for the dye AR.TF.
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