Donato A. G. Aranda

Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil

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Publications (85)202.36 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The search for alternative fuel sources is indispensable to reduce the dependence from petroleum fuels. Biodiesel which is produced from oils and fats is an excellent substitute for diesel. In terms of feedstock, palm oil is highlighted as the traditional culture with best income in oil per hectare and it is one of the most consumed oils in the world. Brazil has great amount of illegally deforested areas in Amazon and these places are able to cultivate palm oil. These areas may be recovered through the palm sustainable planting, developing familiar agriculture and the region׳s economy, besides placing Brazil as one country with highest potential of biodiesel and palm oil production.
    Renewable and Sustainable Energy Reviews 10/2015; 50:1013-1020. DOI:10.1016/j.rser.2015.05.055 · 5.51 Impact Factor
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    ABSTRACT: Algae as a raw material are highly important, since algae have high growth rates and are rich in lipids, proteins, and carotenoids. Direct saponification of alga with an ethanolic solution of KOH or NaOH followed by extraction was investigated and the composition of different fractions was studied by several physico-chemical methods, such as gas- and liquid chromatography, Fourier transform infrared analysis, scanning and transmission electron microscopy, organic elemental analysis, and thermogravimetric analysis. Direct saponification of Chlorella sp. was demonstrated with detailed analysis of different products, such as lipids, proteins, carotenoids and carbohydrates. The yield of lipids and the unsaponifiable fraction was independent on the type and concentration of alkali in direct saponification of green alga Chlorella sp. Proteins were mainly in the solid residue remaining after saponification. Protein content in the solid residue decreased with increasing alkali concentration and the solid residue. The main fatty acids were oleic and linoleic acids. Lutein and β-carotene were the main carotenoids in Chlorella sp. Sugars and large part of proteins remained in the polar fraction after separation of lipid and carotenoids.
    Algal Research 09/2015; 11. DOI:10.1016/j.algal.2015.06.014 · 4.10 Impact Factor
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    ABSTRACT: Nanozeolite NaX ion exchanged with different transition metals (Mn2+,Cu2+, Co2+, Zn2+, Ni2+) was used as a solid support for the immobilization of the lipases of Thermomyces lanuginosus (TLL) and Rhizomucor miehei (RML). The nanozeolite-enzyme complexes were used as heterogeneous catalysts for the transesterification reaction of palm oil to fatty acid ethyl esters (FAEEs). The most relevant results were obtained with the Thermomyces lanuginosus enzyme immobilized on nanozeolitic supports ion exchanged with Ni2+. Although these zeolitic supports were able to immobilize a relatively small amount of the enzyme (43.7%) in comparison with the other nanozeolitic supports, the FAEE yields obtained with Nano-X/Ni/0.5M-TLL complexes were above 94%. These results revealed an unusual synergistic effect between the Thermomyces lanuginosus enzyme and the nickel ion-exchanged nanozeolitic support; this effect was not observed for the complexes prepared with the Rhizomucor miehei enzyme. Bioinformatics calculations were performed for both enzymes by taking into consideration the crystallographic structures of the enzymes and the zeta potential of the surface of the nanozeolitic supports. By combining calculations of the protein electrostatic potential surface and normal mode analyses in a model, we were able to propose an explanation for the synergistic effect between the lipases and the nanozeolitic supports. The synergistic effect could be explained through an allosteric mechanism describing the interaction between aspartic acid residues 102 and 158 of the Thermomyces lanuginosus lipase and the positively charged zeolitic support surface. This interaction results in the stabilization of the opening of the enzyme lid and leaves its catalytic triad permanently exposed to the reaction medium.
    Microporous and Mesoporous Materials 05/2015; 214. DOI:10.1016/j.micromeso.2015.05.007 · 3.21 Impact Factor
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    ABSTRACT: In situ transesterification of Chlorella algae was performed using 5-20 wt% sulfuric acid as a catalyst at either 60 or 100 °C. The maximum ester yield in the range of 96-98% is comparative to the specification of ester content in biodiesel, 96%. A high excess of methanol was used in transesterification ensured also a high ester yield. The FAME was purified via adsorption of chlorophyll and carotenoids onto a clay. Properties of the purified biodiesel were investigated with several methods. The results showed that the Chlorella based biodiesel exhibits slightly lower oxidative and thermal stability compared to soybean based biodiesel due to the presence of polyunsaturated FAMEs. In addition to biodiesel, also the residual biomass was characterized showing that it contained sugars and proteins. An additional hydrogenation would increase the oxidative stability. Hydrodeoxygenation of Chlorella based biodiesel was also demonstrated over 5 wt% Ni-HY-80 zeolite with SiO2/Al2O3 ratio of 80 and with 5 wt% Pd/C at 300 °C and 30 bar in dodecane as a solvent. Ni-HY-80 was superior to Pd/C catalyst giving more than 95% yield of hydrocarbons.
    Fuel 04/2015; 155. DOI:10.1016/j.fuel.2015.03.064 · 3.41 Impact Factor
  • Margarida L. Castelló, Jo Dweck, Donato A. G. Aranda
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    ABSTRACT: ZSM-5 is a zeolite that has been used for decades in catalytic cracking processes, especially in the Brazilian oil industry. This paper investigates thermal analysis of glycerol pyrolysis by means of Kissinger and Ozawa-Flynn-Wall methods and shows activation energy for the reaction. For the experiments, the authors used pure glycerol and a commercial NR4-ZSM-5, which was heated up to 500 °C in order to activate its Brönsted acid sites. In this paper, the authors show, by quantitative thermogravimetry and free kinetic method study, that ZSM-5 can be used as a catalyst for the pyrolysis of glycerol, even at temperatures below 250 °C.
    Journal of Thermal Analysis and Calorimetry 03/2015; 119(3). DOI:10.1007/s10973-014-4365-3 · 2.21 Impact Factor
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    ABSTRACT: This work studies the saponification which directs the wet biomass of algae Chlamydomonas sp. like a previous stage to production of biodiesel. This stage allows the obtainment of fatty acids to produce biodiesel, instead of the gross lipid fraction. In addition of the fatty acids, utilizing the same process one can also obtain the fraction unsaponifiable, these are soluble in apolar solvents and contain mainly carotenoids that can take action as antioxidants and photoprotectors, as they reduce the oxidation of unsaturated fatty acids. The saponification direct and extraction of fatty acids from biomass is faster and reduces the time and cost of operation. The separation of unsa-ponifiable matter from the biomass humid of microalgae Chlamydomonas sp., was held according to the method AOCS (Ca 6a-40), using extraction Liquid-liquid with hexane as solvent. Subse-quently, phase hydroalcoholic or from soap, containing fatty acids, was acidified by addition of H2SO4 and the fatty acids were recovered by the addition of hexane. After acidulation of the soap, necessary for obtaining of the fatty acids was performed the stage of esterification for obtaining of biodiesel. The operating conditions were: molar ratio fatty acid:methanol (1:10), as catalyst 8% H2SO4 calculated in relation to the mass of fatty acid, 200˚C and reaction time of 90 minutes. The content of methyl esters was 96.8% determined by gas chromatography according to standard EN14103. The quality of biodiesel produced from wet biomass of Chlamydomonas sp. is according to the specification established by standard EN 14214 and RANP No. 14. For the identification of the composition the unsaponifiable fraction was used the method of High Performance Liquid G. C. Díaz et al. 1211 Chromatography (HPLC). The composition of the material unsaponifiable found was of: Caro-tenoids total (0.76%); Lutein (0.45%); Zeaxanthin (0.07%); α-carotene (0.05%); β-carotene (0.11%); 13 cisβ-carotene (0.05%) and 9-cisβ-carotene (0.03%).
    Natural Science 09/2014; 6(15):1210-1218. DOI:10.4236/ns.2014.615108
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    ABSTRACT: This work aims at the soybean free fatty acid deoxygenation using palladium supported (1 wt.%) on different clays as catalysts. The results presented a promising technology for the single-stage production of hydrocarbons in the diesel fuel range. Clays used as palladium support were a natural Brazilian Montmorillonite (BM), this same clay in its pillared form (PILCBM) and two commercial clays (K10 and KSF). Catalysts were characterized by N-2 adsorption, X-ray diffraction (XRD), FTIR spectra of adsorbed pyridine, CO chemisorption and scanning electron microscopy (SEM). Reactions were carried out in batch mode, under different H-2 pressures (10, 20, 30 and 40 bar) at 300 degrees C. Reactions performed using Pd/K10 as catalyst at 30 bar of H-2 presented interesting results: 74.5% conversion after 6 h and selectivities to n- and i-alkanes equal to 69% and 29%, respectively.
    Applied Clay Science 06/2014; 95. DOI:10.1016/j.clay.2014.04.026 · 2.70 Impact Factor
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    ABSTRACT: The use of lipids obtained from microalgae biomass has been described as a promising alternative for production of biodiesel to replace petro-diesel. It involves steps such as the cultivation of microalgae, biomass harvesting, extraction and transesterification of lipids. The purpose of the present study was to compare different methods of extracting total lipids. These methods were tested in biomass of Chlorella vulgaris with the solvents ethanol, hexane and a mixture of chloroform:methanol in ratios 1:2 and 2:1. The solvents were associated with other mechanisms of cell disruption such as use of a Potter homogenizer and ultrasound treatment. The percentage of triglycerides in the total lipids was determinated by the glycerol-3-phosphate oxidase-p-chlorophenol method (triglycerides monoreagent K117; Bioclin). Among the tested methods, the mixture of chloroform:methanol (2:1) assisted by ultrasound was most efficient, extracting an average of 19% of total lipids, of which 55% were triglycerides. The gas chromatographic analysis did not show differences in methyl ester profiles of oils extracted under the different methods.
    Ultrasonics Sonochemistry 05/2014; DOI:10.1016/j.ultsonch.2014.05.015 · 4.32 Impact Factor
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    ABSTRACT: In many reactions to produce biodiesel the glycerol represents 10 wt% of the total products therefore it is important to find an adequate destination of such byproduct. The catalytic hydrolysis of triglycerides is another way to produce biodiesel from fatty raw materials. This work shows the catalytic hydrolysis of triglycerides (soybean oil and tallow) with nickel (NiO) or palladium (PdO) catalysts supported on Al2O3 or SiO2. The results showed the direct conversion of in situ generated glycerol into hydrogen (H2) and carbon dioxide (CO2). The glycerol conversion was evaluated through the capacity to hydrogenate the unsaturated fatty acids leading to the formation of stearic acid (saturated compound). The catalyst, temperature and time were varied and evaluated in the experiments utilizing the two different kinds of raw materials (beef tallow and soybean oil). Selectivity and statistical planning studies were performed to optimize the formation of stearic acid as it is linked to the hydrogenation of unsaturated compounds by hydrogen generated from the glycerol liquid reforming.
    Renewable Energy 04/2014; 64:113–122. DOI:10.1016/j.renene.2013.11.006 · 3.36 Impact Factor
  • Engineering 01/2014; 06(01):12-18. DOI:10.4236/eng.2014.61003
  • Journal of Sustainable Bioenergy Systems 01/2014; 04(01):61-67. DOI:10.4236/jsbs.2014.41006
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    ABSTRACT: Polyvinyl alcohol (PVA) microspheres with different degree of crystallinity were used as solid supports for Rhizomucor miehei lipase immobilization, and the enzyme-PVA complexes were used as biocatalysts for the transesterification of soybean oil to fatty acid ethyl esters (FAEE). The amounts of immobilized enzyme on the polymeric supports were similar for both the amorphous microspheres (PVA4) and the high crystalline microspheres (PVA25). However, the enzymatic activity of the immobilized enzymes was depended on the crystallinity degree of the PVA microspheres: enzymes immobilized on the PVA4 microspheres have shown low enzymatic activity (6.13 U mg−1), in comparison with enzymes immobilized on the high crystalline PVA25 microspheres (149.15 U mg−1). A synergistic effect was observed for the enzyme-PVA25 complex during the transesterification reaction of soybean oil to FAEE: transesterification reactions with free enzyme with the equivalent amount of enzyme that were immobilized onto the PVA25 microspheres (5.4 U) have yielded only 20% of FAEE, reactions with the pure highly crystalline microsphere PVA25 have not yielded FAEE, however reactions with the enzyme-PVA25 complexes have yielded 66.3% of FAEE. This synergistic effect of an immobilized enzyme on a polymeric support has not been observed before for transesterification reaction of triacylglycerides into FAEE. Based on ATR-FTIR, 23Na- and 13C-NMR-MAS spectroscopic data and the interaction of the polymeric network intermolecular hydrogen bonds with the lipases residual amino acids a possible explanation for this synergistic effect is provided.
    Biomass and Bioenergy 12/2013; 59. DOI:10.1016/j.biombioe.2013.09.006 · 3.41 Impact Factor
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    ABSTRACT: Biodiesel conventional production process, by alkaline transesterification reaction, have disadvantages such as complex products separation and high feedstock costs. In this regard, production of biodiesel by esterification of fatty acids into a reactive distillation column has proved to be promising for overcoming some of these drawbacks. However, only simulation works that consider only one type of fatty acid reagent are available in the literature, and not simulations based on a real fatty material for this process. In this way, this work presents steady-state computational simulations of fatty acid esters (biodiesel) production in a reactive distillation column by esterification reaction of a new feedstock that represents the fatty acids composition of the soybean oil (hydrolyzed soybean oil) with anhydrous ethanol. Sensitivity analyses showed that the best operating conditions were the minimum reflux ratio of 0.001 and 15 theoretical stages. As to thermal analysis, it was noted that the process is optimized by increasing the energy consumption of reagent instead of the reboiler. The low thermal load on this equipment can be used in order to avoid exposure of the bottom product at elevated temperatures. Conversions close to 99% were possible with the proper choice of these operating conditions. The results show the technical feasibility of this process, and such data can be useful for the design of biodiesel processes.
    Industrial & Engineering Chemistry Research 06/2013; 52(27):9461–9469. DOI:10.1021/ie400806q · 2.24 Impact Factor
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    ABSTRACT: Gismondine (P) ion exchanged with Cu2+, Zn2+, and Ni2+ were used as solid supports for the immobilization of the lipase Rhizomucor miehei enzyme. Physicochemical characterization of the zeolite–enzyme complexes were performed by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and attenuated total reflectance–Fourier transform infrared (ATR–FTIR). These biocatalysts were used for the transesterification reaction of soybean oil to biodiesel. Divalent cation species and thermal treatment of the zeolitic supports had different effects on several parameters under investigation. In terms of the enzyme activity, the zeolite–enzyme complexes prepared with Ni-P were superior in comparison to the other ones and a synergistic effect for the zeolite–enzyme complex (Ni-P/200-ENZ) was observed for the transesterification reactions of soybean oil to biodiesel. The total amount of methyl esters produced by the complex Ni-P/200-ENZ was of 56.2%, while the same concentration of the immobilized enzyme in its free form yielded only 39.3% of methyl esters, and Ni-P/200 in its pure form also yielded a very low amount of methyl esters (20%). The other zeolite–enzyme complexes (Zn-P/200-ENZ, Cu-P/200-ENZ, and Na-P/200-ENZ) presented a completely different behavior in comparison to the Ni-P/200-ENZ complexes. The total yields of methyl esters generated by these biocatalysts were very low and no synergistic effects were observed. A correlation between the cation atomic radius and the enzymatic activity of the zeolite–enzyme complexes was observed. It was noticed that the bigger the atomic radius of the extra-framework cation, smaller was the experimental enzymatic activity coefficient.
    Microporous and Mesoporous Materials 11/2012; 163:343–355. DOI:10.1016/j.micromeso.2012.07.043 · 3.21 Impact Factor
  • Margarida L. Castelló, Jo Dweck, Donato A. G. Aranda
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    ABSTRACT: Over the past years, the production of biodiesel has significantly increased in Brazil due to its obligatory use in the composition of diesel for vehicle use. As a result, in the most ordinary processes, a hundred thousand tons of glycerol is produced as by-product per 1 billion liters of biodiesel. Glycerol has already been widely studied. Nonetheless, the quantity produced today demands new proposals for uses, such as a fuel. In this aim, the authors studied the kinetics of the thermal processing of glycerol. In this research, thermogravimetry (TG), derivative thermogravimetry (DTG), and differential thermal analysis (DTA) were used to provide the experimental data. Kinetic parameters were calculated by Kissinger method for the global process observed during the heating of the samples from the room temperature up to 600 °C, both in open and in sealed crucibles (with a little hole). Kinetic data were also determined at different isoconversion conditions during heating, by applying Ozawa–Flynn–Wall and Blazejowski methods to TG data. Results show that glycerol heated from 30 to 600 °C, under normal pressure, does not experience simple volatilization. The activation energies calculated at different conversion degrees by these methods show that only volatilization occurs when the mass loss of glycerol is lower than 40% and that for higher conversion degrees, partial thermal decomposition and/or dissociation of glycerol are occurring as well. These facts are also confirmed by the volatilization enthalpies estimated using another method developed by Blazejowski based on Van’t Hoff equation.
    Journal of Thermal Analysis and Calorimetry 09/2011; 105(3). DOI:10.1007/s10973-011-1730-3 · 2.21 Impact Factor
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    ABSTRACT: This work presents computational steady-state simulations of fatty acid esters (biodiesel) production in a reactive distillation column. Reaction rates were considered explicitly in the model of each stage. The procedures and formulation used here were initially validated by comparison of simulations results obtained in this work with data available in the literature. Two new cases for fatty acid esters (biodiesel) production are simulated. In both of them, conversions close to 99% are possible with the proper choice of operating conditions, as shown by sensitivity analyses. The simulations results obtained here can be useful for the proper design of processes that use reactive distillation columns for biodiesel production.
    Industrial & Engineering Chemistry Research 07/2011; 50(17):10176–10184. DOI:10.1021/ie102327y · 2.24 Impact Factor
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    ABSTRACT: Biodiesel can be obtained from fatty acid raw materials through esterification. The reactivity of lauric, palmitic, stearic, oleic, and linoleic fatty acids with methanol using powdered niobic acid as a heterogeneous catalyst was investigated in this work, both experimentally (in a batch reactor) and theoretically. A 23 experimental design was used, with methanol/fatty acid molar ratio, catalyst concentration, and temperature as main factors. An empirical model demonstrated that temperature is the most important variable. Fourteen heterogeneous and 56 homogeneous-like kinetic models were tested. A homogeneous-like model considering zero order for all species and inhibition by water was the most adequate for experiments without catalyst. A homogeneous-like model considering a second-order reaction in relation to the fatty acid and no water inhibition was the most adequate for niobic acid catalyzed reaction. Molecular modeling confirmed the experimental results showing that the reactivity is directly related to the increase of unsaturated bonds and the reduction of carbon chain length. The polarity of the fatty acid is determinant in the reactivity. At the molecular level, reaction occurs between the HOMO orbital of methanol and LUMO orbitals of fatty acids and reactivity is higher when the energy difference between these orbitals is lower. Copyright © 2010 John Wiley & Sons, Ltd.
    Journal of Physical Organic Chemistry 01/2011; 24(1). DOI:10.1002/poc.1701 · 1.23 Impact Factor
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    Antonio Carlos Augusto da Costa, Nei Pereira Junior, Donato Alexandre Gomes Aranda
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    ABSTRACT: Biorefinery defines an industrial structure based on the use of biomasses for the production of a wide variety of molecules. Its purpose is to obtain high-cost products from low-cost feedstocks. The stronger candidates for this technology include residual and agro-industrial biomasses. This work includes a review on the state-of-the-art on the production of biofuels in Brazil, as well as the tendencies and present situation of this field in Brazil. These information bring important data for the evaluation on the potential use of biomasses for the production of biofuels, serving as a starting point for a prospective technology for the production of biofuels, based on the use of renewable sources.
    Renewable and Sustainable Energy Reviews 12/2010; 14(9-14):3041-3049. DOI:10.1016/j.rser.2010.07.058 · 5.51 Impact Factor
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    ABSTRACT: Experiments of partial oxidations with molecular oxygen at low temperatures (below 473 K or 200 ºC) were carried out using the linear hydrocarbons n-hexadecane, n-dodecane, n-decane and n-heptane. The analysis of the experimental data obtained showed an increased in the oxygen rate with the increase in the hydrocarbon size, being observed reactions of oxidative cracking with the formation of compounds with small molecular weight. The variation in the oxygen consumption was so small for hydrocarbons higher than C12 (n-dodecane). The reactions of partial oxidation showed autocatalytic behavior in which was observed an increase in the rate of oxidation with the progress of the reaction. From chromatographic analyses of the liquid samples were identified several types of oxygenated compounds and also small amounts of light hydrocarbons, with classes of compounds distributed principally according to the homologous series. The oxidative cracking mechanism can be applied in the recovery of heavy materials as the polymers and the residues of petroleum. Previous experiments with an atmospheric residue of a Brazilian light oil showed promising results related to the higher formation of liquid fraction. The transformation of organic residues into liquid and gaseous products has been the subject of many researches [1]. The plastics and heavy fractions of petroleum represent a serious environmental challenge, since these materials are difficult to be degraded along time, requiring additional costs for their reuse or final disposal. On this way, it is necessary to find new technological alternatives to recovery economically these residues as raw materials to produce valuable substances. The thermal treatment (pyrolysis) is the mostly used technique applied for the processing of organic residues for the production of liquid fuels. Improvements in the conventional thermal processes have been studied through the developments of new technologies as the utilization of new additives [2]. The utilization of oxygen in such processes is a new way to be followed due to the cracking evidences in the pyrolysis studies of polypropylene in the presence of oxygen [2]. From it was observed a great tendency to the formation of light oxygenated compounds from hydroperoxides compounds with a significant decrease on the activation energy of the polymer carbon-carbon bond cleavage when compared to the conventional thermal process (without oxygen). Values of conversion around 70% through photo and thermo decomposition of polypropylene hydroperoxides into gaseous products were obtained in the literature. The experiments of partial oxidations of n-hexadecane, n-dodecane, n-decane and n-heptane at low temperatures (below 473 K or 200 ºC) were performed being determined the consumption rates of oxygen for each paraffin (Fig. 1). The analysis of the experimental samples indicated mechanisms of oxidative cracking with the presence of homologous series. The Fig. 2 shows the GC-MS (Gas Chromatography Mass Spectrometer) mass fragmentogram (m/z 58) of the homologous series of linear aliphatic 2-ketones (from C5 to C9). The utilization of oxygen as an additive in the pyrolisis of an atmospheric residue of a Brazilian light oil showed promising results related to the higher formation of liquid fraction.
    Chemical Engineering Communications 11/2010; 198(3). DOI:10.1080/00986445.2010.512548 · 0.79 Impact Factor
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    ABSTRACT: The process of biodiesel production by the hydroesterification route that is proposed here involves a first step consisting of triacylglyceride hydrolysis catalyzed by lipase from Thermomyces lanuginosus (TL 100L) to generate free fatty acids (FFAs). This step is followed by esterification of the FFAs with alcohol, catalyzed by niobic acid in pellets or without a catalyst. The best result for the enzyme-catalyzed hydrolysis was obtained under reaction conditions of 50% (v/v) soybean oil and 2.3% (v/v) lipase (25 U/mL of reaction medium) in distilled water and at 60°C; an 89% conversion rate to FFAs was obtained after 48 hours of reaction. For the esterification reaction, the best result was with an FFA/methanol molar ratio of 1:3, niobic acid catalyst at a concentration of 20% (w/w FFA), and 200°C, which yielded 92% conversion of FFAs to soy methyl esters after 1 hour of reaction. This study is exceptional because both the hydrolysis and the esterification use a simple reaction medium with high substrate concentrations.
    10/2010; 2011:618692. DOI:10.4061/2011/618692

Publication Stats

929 Citations
202.36 Total Impact Points

Institutions

  • 1993–2015
    • Federal University of Rio de Janeiro
      • • Escola de Química (EQ)
      • • Center of Technology
      Rio de Janeiro, Rio de Janeiro, Brazil
  • 2006
    • Centro Brasileiro de Pesquisas Físicas
      Rio de Janeiro, Rio de Janeiro, Brazil
  • 2004
    • Universidade Aberta do Brasil
      San Paulo, São Paulo, Brazil