Mestrado em Engenharia Química (IQ)
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Navegando Mestrado em Engenharia Química (IQ) por Por Orientador "Freitas, Fernanda Ferreira"
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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 Estudo de co-cultura entre Saccharomyces cerevisiae e Saccharomyces kudriavzevii para elaboração de uma bebida alcoólica fermentada à base de Cagaita (Eugenia dysenterica DC.)(Universidade Federal de Goiás, 2018-08-27) Valério Júnior, Marcos Flávio Ribeiro; Castiglioni, Gabriel Luis; http://lattes.cnpq.br/6050198962131737>; Freitas, Fernanda Ferreira; http://lattes.cnpq.br/0883086742146577; Freitas, Fernanda Ferreira; Castiglioni, Gabriel Luis; Rodriguez, Armando Garcia; Seolatto, Araceli AparecidaThe production of alcoholic ferments from fruit is an attractive alternative for the food industry, as this type of beverage has received strong acceptance from consumers. Climate change and the search for wines with lower alcohol content and a search for a concentration of glycerol and better aromas, led to studies in yeast co-cultures. Brazil is one of the world's largest producers of fruits, including tropical fruit. Among the typical species of Cerrado, Eugenia dysenterica DC, popularly known as Cagaita, is already used in the manufacture of sweets, jellies, ice cream, soft drinks, juices and liqueurs. Regarding the fermenting agent, yeast to Saccharomyces cerevisiae, with high potential for ethanol production, and Saccharomyces kudriavzevii, a notable producer of glycerol, present interesting and required characteristics in the fermented beverage industry. Thus, the present work followed a central rotational experimental planning and a common factorial planning to stipulate the concentration of the strains of Saccharomyces cerevisiae T-73 and Saccharomyces kudriavzevii CR-85, in order to understand how the interaction between the yeasts occurs ethanol, biomass and glycerol responses. From the DCCR, it was not possible to obtain significant models, since experiment 5 where there was pure CR-85 strain did not produce ethanol and glycerol. From these results, it was followed by common factorial planning, in which mathematical models could be obtained for the prediction of ethanol, biomass and glycerol production. It was also possible to identify that the assay with the highest concentration of CR-85 had an increase of glycerol, and the assay with the highest ethanol production was one that contained a slightly higher content of T-73 compared to CR-85. As for the volatile compounds, isoamyl alcohol was identified, responsible for the aromas in the food industry, as well as ethyl acetate, considered an ester acetate that gives the drinks fruit aromas. This research also presents details of the kinetics of growth, substrate consumption and production of Saccharomyces cerevisiae T-73 and Saccharomyces kudriavzevii CR-85 yeast products, in which the characteristics inherent to each yeast can influence the behavior of the kinetic parameters, characterizing the need to deepen studies on the metabolism of these yeasts.