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URI permanente para esta coleçãohttps://repositorio.fei.edu.br/handle/FEI/5135

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DMLM III device development for enzymes biochemical reactions in microgravity
(2011-05-22) LA NEVE, A.; BELLODI, M.; MELO, M. A. A.; FERREIRA, M.; PEREIRA, A. N.; LUCARINI, A. C.
The goal of this experiment was to investigate the invertase enzyme kinetics in microgravity to better understand the mechanism action inside and outside biological cells. To do this DMLM 111 device was developed, which is responsible for mixing liquids in microgravity. It consists of a mechanical part, with ten sets of reaction systems, and embedded electronics. Each reaction system consists of three chambers, for the enzyme, the substrate and the reaction inhibitor, and two valves to keep the liquids separated. When microgravity signal is triggered, enzyme and substrate are mixed to start the biochemical reaction. After five minutes the reaction is interrupted with the inhibitor. This experiment was embedded on a VSB-30 Brazilian sounding rocket, and payload remained in microgravity for approximately six minutes. Biochemical analyses of the samples are under way, and the results will be compared with the data obtained on earth, under similar conditions.
CIM device for enzyme kinetics experiment aboard the International Space Station
(2011-10-03) LA NEVE, A.; BELLODI, M.; FERREIRA, M.; LUCARINI, A. C.
The main objective of this experiment is to verify the differences in kinetic parameters of enzymes reaction aboard the ISS. For this experiment the invertase enzyme was selected, as a case study in microgravity. It is expected that significant differences occur in the sucrose hydrolysis by invertase, due to diffusion phenomenon in microgravity. The experiment consists of two series of tests, each one with five different sucrose concentrations, to evaluate the invertase kinetics. The reaction is allowed during a period of time, after which the reactions are interrupted by addition of an enzyme inhibitor. The samples of the enzymes, after reaction, must return to earth for biochemical analysis in laboratory. It is expected that significant differences should occur in the hydrolysis of sucrose by invertase, due the diffusion phenomenon, that suffers alterations in microgravity. To perform this experiment in microgravity on ISS, CIM device was developed, with two sets of 5 chambers each, in a total of 10, to realize the mixture of two liquids and the enzyme. This compact device requires no electric power, and it can easily be operated by an astronaut manually. This device is an important evolution over the previous version, MEK device, which flew on ISS Brazilian "Centenary Mission", in March, 2006. The results were partly satisfactory and indicated an increase in reaction rate values, but a metal contamination of the samples due to the resistor oxidation, interfered in the biochemical reaction: this required confirmation and of the experiment and confrontation of data. This experiment aims at the study of the enzymatic kinetics of invertase, which catalyzes carbohydrates hydrolysis, such as sucrose, producing glucose and fructose. The study of enzymatic kinetics is fundamental for the comprehension of the enzymes action mechanism, in and out of the cells, and this may lead to the design of more efficient enzymatic bioreactors. Therefore, the study of the effects of microgravity on the enzymes action can be helpful to better understand their action mechanism on earth, and then to think of enzymatic processes and microorganisms applications, both on earth and in space. Copyright ©2010 by the International Astonautical Federation. All rights reserved.
Biodiesel production from vegetal oil and ethanolvia transesterification in supercritical conditions
(2014-11-16) SIDI NETO, V.; João Guilherme Rocha Poço
Density and speed of sound of binary mixtures of (diethyl malonate + methanol) at different temperatures and atmospheric pressure
(2014-11-16) LIBORIO, M. N.; Ricardo Torres
Influence of feedstock on biodiesel corrosiveness and degradation
(2014-11-16) Isabella Aquino; ALVES, T. P.; SILVA, F. F. R; AOKI, I. V.; Ricardo Torres
Transesterification of sunflower oil produced by solvent extraction
(2014-11-16) Maristhela Passoni de Araújo Marin; Luis Novazzi; DENARI, M. L.
In this work, the leaching of oil from sunflower seeds using hexane was studied. The solution of oil / hexane was thereafter transesterified, with methanol and potassium hydroxide (KOH) as the catalyst, in a batch reactor, for 1 hour and with a constant temperature of 45 °C. It is important to point out that the extracted oil was not refined and was directly used on transesterification reactions. The hexane in the oil / hexane solution acted as a cosolvent and made the oil / methanol mixture forms a single-phase. Experimental results obtained in the transesterification reactions showed that the increase of methanol / oil mole ratio on reaction yield is negative, whereas the increase of catalyst concentration on reaction yield is positive. Reaction yields decreased 18.00% on average when the mole ratio methanol / oil was increased. When catalyst concentration was augmented, reaction yields increased 15.19%, on average. These results are statistically meaningful, since the standard deviation was equal to 0.48%. Moreover, an interaction between methanol / oil mole ratio and catalyst concentration on reaction yield was observed.
Biodiesel production from vegetal oil and ethanol via transesterification in supercritical conditions
(2014-11-16) SIDI NETO, V.; João Guilherme Rocha Poço
Use of cellular ceramic-supported SrO as a catalyst for the synthesis of biodiesel
(2014-01-27) BASSETTI, F. B.; Andreia de Araújo Morandim Giannetti; F. S. Ortega
One of the most common methods for the production of biodiesel is the transesterification of oils in the presence of methanol and a catalyst. The catalysts may be homogeneous or heterogeneous, with the latter consuming less energy, being reusable, thus more environmentally attractive. Although there are many studies on the use of alkaline earth oxides as heterogeneous catalysts for the synthesis of biodiesel, few papers deal with the use of strontium oxide. Additionally, these catalysts have been studied as particles dispersed in the reaction medium. This study investigates the potential use of strontium oxide as a catalyst for the synthesis of biodiesel, initially as a particulate material, under various temperatures and catalyst concentrations in the reaction medium. The results showed that the strontium oxide is a potential catalyst, reaching up to 58% conversion. In a second step, a thin film of strontium oxide was deposited on a catalyst support consisting of a cylinder of cellular alumina produced by direct foaming of a suspension, followed by heating at 1500°C for 2 hours. This impregnated foam was used as the core of a plug flow reactor prototype for the synthesis of biodiesel. With this prototype it was possible to achieve up to 90% of conversion of soy oil and methanol into biodiesel, after 3 hours. This result discloses the potential of this new approach for the synthesis of biodiesel.
Alternative method for bulk solids time flow function estimation
(2015-11-08) Rodrigo Condotta; DE RYCK, A.
The use of dimethyl carbonate for etherification
(2015-11-08) Rodrigo Cella; TABU, A. S. T. Z.

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