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Camila Da Silva - One of the best experts on this subject based on the ideXlab platform.
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sequential process for obtaining Methyl esters and triacetin from crambe oil using pressurized Methyl Acetate
Industrial Crops and Products, 2020Co-Authors: Bruna Tais Ferreira De Mello, Caroline Portilho Trentini, Najla Postaue, Camila Da SilvaAbstract:Abstract The aim of this study was to investigate the application of a sequential process for the production of fatty acid Methyl esters (FAME) and triacetin (TA) from crambe seeds using Methyl Acetate (MA) under pressurized conditions. In this process, Methyl Acetate acts as an extraction solvent and an acyl acceptor for the conversion of the oil to the products of interest. The initial step was pressurized liquid extraction (PLE) performed in a semi-continuous experiment (140 °C and 10 MPa) and material resulting from this step (oil+MA) was directed to a continuous reaction unit. The tests were performed with different pressures, temperatures and residence times. Reactions with commercial oil (CO) were evaluated for comparison. According to the data obtained, increasing the pressure to 20 MPa resulted in higher FAME yields (YFAME) and TA contents for both oils tested. In the reaction with the PLE mixture an increase in temperature favored the formation of FAME and a yield of 66.49 % was achieved at 375 °C after 15 min. The TA content was highest at 325 °C and 5.01 wt% of this coproduct was obtained after 35 min. At the other temperatures, an increase in the TA content was not observed after 15 min. The results obtained in the reactions with CO demonstrated lower than those for the oil obtained by PLE and the reduction of polyunsaturated esters was more evident in the reaction products of this oil. At 375 °C, the increase in residence time provided higher conversion of triglycerides and free fatty acids, as well as higher consumption of intermediate reaction compounds, and enhanced levels of thermal degradation. Thus, the results point to the benefits of using the sequential process to obtain FAME and TA in terms of yield and reduction of the decomposed fraction.
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use of heterogeneous acid catalyst combined with pressurized conditions for esters production from macauba pulp oil and Methyl Acetate
Journal of Supercritical Fluids, 2019Co-Authors: Luiz Jardel Visioli, Fernanda De Castilhos, Camila Da SilvaAbstract:Abstract The objective of this work was to evaluate the production of fatty acid Methyl esters using macauba oil and Methyl Acetate under pressurized conditions, using heterogeneous γ-alumina catalyst in a continuous system. The catalytic reaction kinetics were evaluated at temperatures between 225 and 300 °C, as well as the effect of catalyst particle size on the reaction. The temperature increase promoted an esters and triacetin (TA) production rise. It was found that the catalyst utilization, in granulometry from 0.85 to 1.00 mm, allowed better product yields at shorter residence time. The best result for catalytic reaction was obtained using the smallest catalyst particle size (0.85–1 mm), 275 °C, 20 MPa, Methyl Acetate (MA):oil mass ratio of 2.5:1, 20 min, obtaining 60.24 ± 0.68% esters content and 2.76 ± 0.06% TA content. The heterogeneous catalyst usage increased the TA production by 736% and the esters production by 33%.
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Methyl Acetate as solvent in pressurized liquid extraction of crambe seed oil
Journal of Supercritical Fluids, 2019Co-Authors: Bruna Tais Ferreira De Mello, Isabela Julio Iwassa, Roberta Pazinato Cuco, Vitor Augusto Dos Santos Garcia, Camila Da SilvaAbstract:Abstract The aim of this study was to evaluate the efficiency of Methyl Acetate as a solvent in the pressurized liquid extraction (PLE) of crambe seed oil. The extractions were conducted in an experimental apparatus operated in semi-continuous mode and the effects of solvent flow and temperature on the yield and quality of the oil obtained were evaluated. The results were compared with those for oil obtained from Soxhlet extraction method and a commercial sample. An increase in the solvent flow and in the temperature promoted a greater removal of oil from seeds under pressurized conditions and a yield of 49.1% was achieved. The fatty acids composition was not influenced by the methods evaluated and the oil convertibility decreased with the use of higher temperatures. The oil extracted by PLE presented higher concentrations of phytosterols and tocopherols, as well as high resistance to oxidation compared to the oil from Soxhlet method.
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synthesis of Methyl esters and triacetin from macaw oil acrocomia aculeata and Methyl Acetate over γ alumina
Industrial Crops and Products, 2018Co-Authors: J S Ribeiro, Camila Da Silva, Dian Celante, L N Brondani, Debora O Trojahn, Fernanda De CastilhosAbstract:Abstract Glycerol excess in the market and high cost of common feedstock have encouraged the investigations of new technologies for biodiesel production. In this context, the use of macaw oil (Acrocomia aculeata) for biodiesel production through interesterification and esterification reactions with Methyl Acetate as acyl acceptor was evaluated, using heterogeneous catalyst γ-alumina (γ-Al2O3). Experiments were performed at different reaction temperatures (225–300 °C), catalyst contents (0–10% relation to oil mass), oil to Methyl Acetate molar ratios (1:10–1:40) and reaction times in a batch reactor to determine the effect of these variables in FAME (fatty acid Methyl esters) and triacetin production. Catalyst γ-Al2O3 improved FAME and triacetin contents in comparison with no catalyzed reaction. Reaction at 300 °C, with 2% of catalyst in relation to oil mass and molar ratio of 1:20, in 60 min provided the best results. The catalyst could be recovered and reused for at least 6 cycles without significant activity loss. The results allowed to point out that the process showed to be promising for industrial biodiesel production with no glycerol and was financial attractive, since it used a low cost feedstock.
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Esters production in continuous reactor from macauba pulp oil using Methyl Acetate in pressurized conditions
The Journal of Supercritical Fluids, 2018Co-Authors: Luiz Jardel Visioli, Caroline Portilho Trentini, Fernanda De Castilhos, Camila Da SilvaAbstract:Abstract This study aims to produce fatty acid Methyl esters and triacetin from macauba pulp oil and Methyl Acetate (MA) in pressurized conditions in a continuous reactor. A Box-Behnken experimental design for temperature, pressure and MA:oil mass ratio variables was applied. Distinct behaviors were observed for fatty acid Methyl esters and triacetin formation. Increase in reaction temperature result improved both in esters and triacetin content. It was observed that increase in pressure favored fatty acid Methyl esters production between 15 and 20 MPa more significantly. Besides that, increase in MA:oil mass ratio raised triacetin content at high reaction temperatures. The highest ester yield observed was 81.2% at 20 MPa, 325 °C and MA:oil mass ratio of 1:1. Reaction kinetic was evaluated in different temperatures (225 °C– 350 °C) at 20 MPa of pressure and MA:oil mass ratio of 1:2.5.
Fernanda De Castilhos - One of the best experts on this subject based on the ideXlab platform.
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use of heterogeneous acid catalyst combined with pressurized conditions for esters production from macauba pulp oil and Methyl Acetate
Journal of Supercritical Fluids, 2019Co-Authors: Luiz Jardel Visioli, Fernanda De Castilhos, Camila Da SilvaAbstract:Abstract The objective of this work was to evaluate the production of fatty acid Methyl esters using macauba oil and Methyl Acetate under pressurized conditions, using heterogeneous γ-alumina catalyst in a continuous system. The catalytic reaction kinetics were evaluated at temperatures between 225 and 300 °C, as well as the effect of catalyst particle size on the reaction. The temperature increase promoted an esters and triacetin (TA) production rise. It was found that the catalyst utilization, in granulometry from 0.85 to 1.00 mm, allowed better product yields at shorter residence time. The best result for catalytic reaction was obtained using the smallest catalyst particle size (0.85–1 mm), 275 °C, 20 MPa, Methyl Acetate (MA):oil mass ratio of 2.5:1, 20 min, obtaining 60.24 ± 0.68% esters content and 2.76 ± 0.06% TA content. The heterogeneous catalyst usage increased the TA production by 736% and the esters production by 33%.
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synthesis of Methyl esters and triacetin from macaw oil acrocomia aculeata and Methyl Acetate over γ alumina
Industrial Crops and Products, 2018Co-Authors: J S Ribeiro, Camila Da Silva, Dian Celante, L N Brondani, Debora O Trojahn, Fernanda De CastilhosAbstract:Abstract Glycerol excess in the market and high cost of common feedstock have encouraged the investigations of new technologies for biodiesel production. In this context, the use of macaw oil (Acrocomia aculeata) for biodiesel production through interesterification and esterification reactions with Methyl Acetate as acyl acceptor was evaluated, using heterogeneous catalyst γ-alumina (γ-Al2O3). Experiments were performed at different reaction temperatures (225–300 °C), catalyst contents (0–10% relation to oil mass), oil to Methyl Acetate molar ratios (1:10–1:40) and reaction times in a batch reactor to determine the effect of these variables in FAME (fatty acid Methyl esters) and triacetin production. Catalyst γ-Al2O3 improved FAME and triacetin contents in comparison with no catalyzed reaction. Reaction at 300 °C, with 2% of catalyst in relation to oil mass and molar ratio of 1:20, in 60 min provided the best results. The catalyst could be recovered and reused for at least 6 cycles without significant activity loss. The results allowed to point out that the process showed to be promising for industrial biodiesel production with no glycerol and was financial attractive, since it used a low cost feedstock.
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Esters production in continuous reactor from macauba pulp oil using Methyl Acetate in pressurized conditions
The Journal of Supercritical Fluids, 2018Co-Authors: Luiz Jardel Visioli, Caroline Portilho Trentini, Fernanda De Castilhos, Camila Da SilvaAbstract:Abstract This study aims to produce fatty acid Methyl esters and triacetin from macauba pulp oil and Methyl Acetate (MA) in pressurized conditions in a continuous reactor. A Box-Behnken experimental design for temperature, pressure and MA:oil mass ratio variables was applied. Distinct behaviors were observed for fatty acid Methyl esters and triacetin formation. Increase in reaction temperature result improved both in esters and triacetin content. It was observed that increase in pressure favored fatty acid Methyl esters production between 15 and 20 MPa more significantly. Besides that, increase in MA:oil mass ratio raised triacetin content at high reaction temperatures. The highest ester yield observed was 81.2% at 20 MPa, 325 °C and MA:oil mass ratio of 1:1. Reaction kinetic was evaluated in different temperatures (225 °C– 350 °C) at 20 MPa of pressure and MA:oil mass ratio of 1:2.5.
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efficiency of heterogeneous catalysts in interesterification reaction from macaw oil acrocomia aculeata and Methyl Acetate
Fuel, 2017Co-Authors: J S Ribeiro, Camila Da Silva, Dian Celante, Santhiago Scherer Simoes, Mariana M Bassaco, Fernanda De CastilhosAbstract:Abstract Heterogeneous catalysts (niobium phosphate, niobium oxide, γ-alumina and zeolite HY) have been evaluated in interesterification reaction of macaw oil with Methyl Acetate, to produce fatty acid Methyl esters (FAME) and triacetin. The reaction was conducted with a Methyl Acetate to oil molar ratio of 30:1, 5 wt% of catalyst and 250 °C. All the catalysts, except zeolite HY, exhibited good catalytic activity, and the most suitable were γ-alumina and niobium phosphate, that reached a FAME and triacetin content of 51.60 wt% and 53.55%, respectively, in 2 h, which considering the maximum oil convertibility of 61.6 wt%, corresponds to 83.77 wt% and 86.93 wt% of conversion efficiency, respectively. The effect of reaction time was studied for these catalysts and it was observed that for γ-alumina one hour of reaction was enough to reach 52.49 wt% of FAME and triacetin yield, corresponding to 85.21 wt% of conversion efficiency. On the other hand, in reaction with niobium phosphate two hours and a half were required to achieve 52.90 wt% of FAME and triacetin yield, corresponding to 85.87 wt% of conversion efficiency. γ-alumina could be reused for at least 5 cycles without great activity loss, while niobium phosphate presented significant activity loss from the first to the second cycle.
Martin Aznar - One of the best experts on this subject based on the ideXlab platform.
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density refraction index and vapor liquid equilibria of n Methyl 2 hydroxyethylammonium hexanoate plus Methyl Acetate ethyl Acetate or propyl Acetate at several temperatures
Industrial & Engineering Chemistry Research, 2012Co-Authors: Victor H Alvarez, Silvana Mattedi, Martin AznarAbstract:This paper reports the densities, refraction indices, and vapor liquid equilibria for binary systems ester + n-Methyl2-hydroxyethylammonium hexanoate (m-2-HEAH): Methyl Acetate (1) + m-2-HEAH (2), ethyl Acetate (1) + m-2-HEAH, and propyl Acetate (1) + m-2-HEAH (2). The excess molar volumes, deviations in the refraction index, apparent molar volume, and thermal expansion coefficient for the binary systems were fitted to polynomial equations. The Peng—Robinson equation of state, coupled with the Wong―Sandler mixing rule, is used to describe the experimental data. Since the predictive activity coefficient model COSMO-SAC is used in the Wong—Sandler mixing rule, the resulting thermodynamic model is a completely predictive one. The prediction results for the density and for the vapor―liquid equilibria have a deviation lower than 1.6% and 1.1%, respectively.
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density refraction index and vapor liquid equilibria of n Methyl 2 hydroxyethylammonium hexanoate plus Methyl Acetate ethyl Acetate or propyl Acetate at several temperatures
Industrial & Engineering Chemistry Research, 2012Co-Authors: V Alvarez, Silvana Mattedi, Martin AznarAbstract:This pap er reports the densities, refraction indices, and vapor liquid equilibria for binary systems ester + N-Methyl-2-hydroxyethylammonium butyrat e (m-2-HEAB): Methyl Acetate (1) + m-2-HEAB (2), ethyl Acetate (1) + m-2-HEAB and propy l Acetate (1) + m-2-HEAB (2). The excess molar volumes, deviations in the refraction index, apparent molar volumes, and thermal expansion coefficients for the binary systems were fitted to polynomial equations. The Peng–Robinson equation of state, coupled with the Wong–Sandler mixing rule, is used to describe the experimen tal data. Since the predictive activity coefficient model COSMO-SAC is used in the Wong–Sandler mixing rule, the resulting thermodynamic model is a completely predictive one. The prediction results for the density and for the vapor–liquid equilibria have a deviation lower than 1.0% and 1.1%, respectively.
Phillip R Westmoreland - One of the best experts on this subject based on the ideXlab platform.
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isomer specific fuel destruction pathways in rich flames of Methyl Acetate and ethyl formate and consequences for the combustion chemistry of esters
Journal of Physical Chemistry A, 2007Co-Authors: Patrick Osswald, Ulf Struckmeier, Tina Kasper, Katharina Kohsehoinghaus, Juan Wang, Terrill A Cool, Nils Hansen, Phillip R WestmorelandAbstract:The influences of fuel-specific destruction pathways on flame chemistry are determined for two isomeric ester fuels, Methyl Acetate, CH3(CO)OCH3, and ethyl formate, H(CO)OC2H5, used as model representatives for biodiesel compounds, and their potential for forming air pollutants is addressed. Measurements are presented of major and intermediate species mole fractions in premixed, laminar flat flames using molecular-beam sampling and isomer-selective VUV-photoionization mass spectrometry. The observed intermediate species concentrations depend crucially on decomposition of the different radicals formed initially from the fuels. The Methyl Acetate structure leads to preferential formation of formaldehyde, while the ethyl formate isomer favors the production of acetaldehyde. Ethyl formate also yields higher concentrations of the C2 species (C2H2 and C2H4) and C4 species (C4H2 and C4H4). Benzene concentrations, while larger for ethyl formate, are at least an order of magnitude smaller for both flames than seen...
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isomer specific fuel destruction pathways in rich flames of Methyl Acetate and ethyl formate and consequences for the combustion chemistry of esters
Journal of Physical Chemistry A, 2007Co-Authors: Patrick Osswald, Ulf Struckmeier, Tina Kasper, Katharina Kohsehoinghaus, Juan Wang, Terrill A Cool, Nils Hansen, Phillip R WestmorelandAbstract:The influences of fuel-specific destruction pathways on flame chemistry are determined for two isomeric ester fuels, Methyl Acetate, CH3(CO)OCH3, and ethyl formate, H(CO)OC2H5, used as model representatives for biodiesel compounds, and their potential for forming air pollutants is addressed. Measurements are presented of major and intermediate species mole fractions in premixed, laminar flat flames using molecular-beam sampling and isomer-selective VUV-photoionization mass spectrometry. The observed intermediate species concentrations depend crucially on decomposition of the different radicals formed initially from the fuels. The Methyl Acetate structure leads to preferential formation of formaldehyde, while the ethyl formate isomer favors the production of acetaldehyde. Ethyl formate also yields higher concentrations of the C2 species (C2H2 and C2H4) and C4 species (C4H2 and C4H4). Benzene concentrations, while larger for ethyl formate, are at least an order of magnitude smaller for both flames than seen for simple hydrocarbon fuels (ethylene, ethane, propene, and propane).
Sandip K., Chakrabarti - One of the best experts on this subject based on the ideXlab platform.
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Methyl Acetate and its singly deuterated isotopomers in the interstellar medium
The Astrophysical Journal, 2015Co-Authors: Ankan, Das, Liton Majumdar, Dipen, Sahu, Prasanta, Gorai, B, Sivaraman, Sandip K., ChakrabartiAbstract:Methyl Acetate (CH3COOCH3) has been recently observed by IRAM 30 m radio telescope in Orion though the presence of its deuterated isotopomers is yet to be confirmed. We therefore study the properties of various forms of Methyl Acetate, namely, CH3COOCH3, CH2DCOOCH3 and CH3COOCH2D. Our simulation reveals that these species could be produced efficiently both in gas as well as in ice phases. Production of Methyl Acetate could follow radical-radical reaction between acetyl (CH3CO) and methoxy (CH3O) radicals. To predict abundances of CH3COOCH3 along with its two singly deuterated isotopomers and its two isomers (ethyl formate and hydroxyacetone), we prepare a gasgrain chemical network to study chemical evolution of these molecules. Since gas phase rate coefficients for Methyl Acetate and its related species were unknown, either we consider similar rate coefficients for similar types of reactions (by following existing data bases) or we carry out quantum chemical calculations to estimate the unknown rate coefficients. For the surface reactions, we use adsorption energies of reactants from some earlier studies. Moreover, we perform quantum chemical calculations to obtain spectral properties of Methyl Acetate in infrared and sub-millimeter regions. We prepare two catalog files for the rotational transitions of CH2DCOOCH3 and CH3COOCH2D in JPL format, which could be useful for their detection in regions of interstellar media where CH3COOCH3 has already been observed. Subject headings: Astrochemistry, spectra, ISM: molecules, ISM: abundances, ISM: evolution, methods: numerical
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Methyl Acetate and its singly deuterated isotopomers in the interstellar medium
The Astrophysical Journal, 2015Co-Authors: Ankan, Das, Liton Majumdar, Dipen, Sahu, Prasanta, Gorai, B, Sivaraman, Sandip K., ChakrabartiAbstract:Methyl Acetate (CH_3COOCH_3) has been recently observed by IRAM 30 m radio telescope in Orion though the presence of its deuterated isotopomers is yet to be confirmed. We therefore study the properties of various forms of Methyl Acetate, namely, CH_3COOCH_3, CH_2DCOOCH_3 and CH_3COOCH_2D. Our simulation reveals that these species could be produced efficiently both in gas as well as in ice phases. Production of Methyl Acetate could follow radical-radical reaction between acetyl (CH_3CO) and methoxy (CH_3O) radicals. To predict abundances of CH_3COOCH_3 along with its two singly deuterated isotopomers and its two isomers (ethyl formate and hydroxyacetone), we prepare a gas-grain chemical network to study chemical evolution of these molecules. Since gas phase rate coefficients for Methyl Acetate and its related species were unknown, either we consider similar rate coefficients for similar types of reactions (by following existing data bases) or we carry out quantum chemical calculations to estimate the unknown rate coefficients. For the surface reactions, we use adsorption energies of reactants from some earlier studies. Moreover, we perform quantum chemical calculations to obtain spectral properties of Methyl Acetate in infrared and sub-millimeter regions. We prepare two catalog files for the rotational transitions of CH_2DCOOCH_3 and CH_3COOCH_2D in JPL format, which could be useful for their detection in regions of interstellar media where CH_3COOCH_3 has already been observed.