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Navegando Programa de Pós-graduação em Engenharia Química por Assunto "Adsorption"
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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 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 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 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 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.