Mestrado em Engenharia Química (IQ)
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Navegando Mestrado em Engenharia Química (IQ) por Por Orientador "Seolatto, Araceli Aparecida"
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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 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.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.