scholarly journals Esterification of Free Fatty Acids with Glycerol within the Biodiesel Production Framework

Processes ◽  
2019 ◽  
Vol 7 (11) ◽  
pp. 832 ◽  
Author(s):  
Juan Francisco García Martín ◽  
Javier Carrión Ruiz ◽  
Miguel Torres García ◽  
Chao-Hui Feng ◽  
Paloma Álvarez Mateos

Companies in the field of the collection and treatment of waste cooking oils (WCO) for subsequent biodiesel production usually have to cope with high acidity oils, which cannot be directly transformed into fatty acid methyl esters due to soap production. Since glycerine is the main byproduct of biodiesel production, these high acidity oils could be esterified with the glycerine surplus to transform the free fatty acids (FFA) into triglycerides before performing the transesterification. In this work, commercial glycerol was esterified with commercial fatty acids and commercial fatty acid/lampante olive oil mixtures over tin (II) chloride. In the first set of experiments, the esterification of linoleic acid with glycerol excess from 20 to 80% molar over the stoichiometric was performed. From 20% glycerol excess, there was no improvement in FFA reduction. Using 20% glycerol excess, the performance of a biochar obtained from heavy metal-contaminated plant roots was compared to that of SnCl2. Then, the effect of the initial FFA content was assessed using different oleic acid/lampante olive oil mixtures. The results illustrated that glycerolysis was impeded at initial FFA contents lower than 10%. Finally, the glycerolysis of a WCO with 9.94% FFA was assayed, without success.

2011 ◽  
Vol 77 (22) ◽  
pp. 8052-8061 ◽  
Author(s):  
Parwez Nawabi ◽  
Stefan Bauer ◽  
Nikos Kyrpides ◽  
Athanasios Lykidis

ABSTRACTThe production of low-cost biofuels in engineered microorganisms is of great interest due to the continual increase in the world's energy demands. Biodiesel is a renewable fuel that can potentially be produced in microbes cost-effectively. Fatty acid methyl esters (FAMEs) are a common component of biodiesel and can be synthesized from either triacylglycerol or free fatty acids (FFAs). Here we report the identification of a novel bacterial fatty acid methyltransferase (FAMT) that catalyzes the formation of FAMEs and 3-hydroxyl fatty acid methyl esters (3-OH-FAMEs) from the respective free acids andS-adenosylmethionine (AdoMet). FAMT exhibits a higher specificity toward 3-hydroxy free fatty acids (3-OH-FFAs) than FFAs, synthesizing 3-hydroxy fatty acid methyl esters (3-OH-FAMEs)in vivo. We have also identified bacterial members of the fatty acyl-acyl carrier protein (ACP) thioesterase (FAT) enzyme family with distinct acyl chain specificities. These bacterial FATs exhibit increased specificity toward 3-hydroxyacyl-ACP, generating 3-OH-FFAs, which can subsequently be utilized by FAMTs to produce 3-OH-FAMEs. PhaG (3-hydroxyacyl ACP:coenzyme A [CoA] transacylase) constitutes an alternative route to 3-OH-FFA synthesis; the coexpression of PhaG with FAMT led to the highest level of accumulation of 3-OH-FAMEs and FAMEs. The availability of AdoMet, the second substrate for FAMT, is an important factor regulating the amount of methyl esters produced by bacterial cells. Our results indicate that the deletion of the global methionine regulatormetJand the overexpression of methionine adenosyltransferase result in increased methyl ester synthesis.


2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Alexander M. Wathne ◽  
Hanne Devle ◽  
Carl Fredrik Naess-Andresen ◽  
Dag Ekeberg

Fatty acid (FA) profiles of the species Tettigonia viridissima, Chorthippus biguttulus, and Chorthippus brunneus were determined and quantitated. Extracted lipids were derivatized into FA methyl esters (FAMEs) prior to analysis by GC-MS. A total of 37 different FAs were identified in T. viridissima, yielding a total FA content of 10.4 g/100 g of dry matter. The contents of saturated FAs, monounsaturated FAs, and polyunsaturated FAs were 31.1, 35.9, and 33.0%, respectively. Lipids from T. viridissima were also fractioned into neutral lipids, free fatty acids, and polar lipids by offline solid phase extraction. For C. brunneus and C. biguttulus, 33 FAs were identified, yielding a total FA content of 6.14 g/100 g of dry matter. SFAs, MUFAs, and PUFAs, respectively, constituted 32.7, 25.1, and 42.1% of the total FA content. The contents of MUFAs, PUFAs, n-3 FAs, and n-6 FAs of each species, and the n-6/n-3 ratio, were subsequently discussed.


Author(s):  
Maira Alejandra Maquirriain ◽  
Lucas Gabriel Tonutti ◽  
Carlos Alberto Querini ◽  
María Laura Pisarello

Author(s):  
Elsy Arenas ◽  
Aidin Urribarrí ◽  
John Sánchez ◽  
Marisela Rincón ◽  
Karina Martínez ◽  
...  

Large quantities of used vegetable oils (AVUs) are generated annually, as a result of food preparation, which can cause contamination of waters and soils, if they are not disposed of properly, but in turn have great potential in the production of biodiesel. In this work, the AVU collected from fast food establishments were subjected to an esterification pretreatment, varying the reaction conditions, molar ratio, catalyst concentration and time, to decrease the content of free fatty acids generated in the frying processes; after an alkaline transesterification. The initial acidity of the AVUs (10,08 ± 0,22 %) was found to drop below 1 % during esterification at 60 °C and 100 rpm, with RMAVU:MeOH of 1: 7 and HCl concentration of 0.3 % v/v, with a conversion of free fatty acids (FFA) to methyl esters of 94.48 and 98.61 % for reaction times of 4 and 6 hours, respectively. The previously esterified AVUs were subjected to a transesterification process with KOH as a catalyst in the presence of methanol, at 60 °C and 100 rpm, finding that the biodiesel produced was a mixture composed of the methyl esters of linoleic acids (57 %), palmitic (14 %), oleic (22 %), stearic (4 %) and elaidic (3 %). The highest concentration of methyl esters (93,797 ± 0.685 g.L-1) was obtained when using the esterified AVU during 6 hours of reaction. FTIR spectra confirmed the conversion of fatty acids to methyl esters, so this product could be used as a biofuel.


2015 ◽  
Vol 9 (1) ◽  
pp. 5-13 ◽  
Author(s):  
Angelo Liguori ◽  
Emilia Lucia Belsito ◽  
Maria Luisa Di Gioia ◽  
Antonella Leggio ◽  
Francesca Malagrinò ◽  
...  

The present investigation reports a study about the evolution, during ripening, of the fatty acid profile and the fatty acid composition in acylglycerols of three different fermented sausages industrially produced in the Calabria region (Southern Italy). Statistical analysis (ANOVA) was applied to the results obtained for the profiles to check all the differences between samples. The study comprised also an evaluation of the lipid oxidation level. All kind of sausages showed a free fatty acids profile in which the monounsaturated fatty acids were predominant, followed by saturated and polyunsaturated fatty acids. In acylglycerols, a low content in linoleic acid (approximately 2% of total methyl esters) was displayed, while that found in the free fatty acids profile was higher (approximately 17% of total FFAs). In addition, the generation of aldehydes through secondary lipid oxidation was clearly confirmed after long ripening period by classical qualitative colorimetric method supported by 1H NMR spectroscopy. The differences in fatty acids profiles observed in the free fatty acids and the acylglycerol fractions were certainly due to the high selectivity of lypase activity during the ripening.


2014 ◽  
Vol 13 (1) ◽  
pp. 31
Author(s):  
Avita Kusuma Wardhani ◽  
Chusnul Hidayat

Fatty acid methyl esters (FAME) are produced by transesterification. The problem in the product of transesterification is the presence of impurities such as mono-, di-, triglycerides, and free fatty acids. So that, the purification using solvent fractionation is needed to separate them from FAME. The objective of this research were to determine the effects of crude fatty acid methyl esters-to-acetone (CFAME/acetone) ratio on yield, purity, purification factor, and recovery of FAME after fractionation and to evaluate the impurities which were separated in each step of fractionation. FAME were produced from Jatropha curcas oil using Berchmans’s and Tiwari’s methods. The impurities were separated by solvent fractionation using acetone. CFAME/acetone ratios were 1, 2, 3, 4, and 5. Fractionation was done stepwise namely 21°C, 16°C, 12°C, and 5°C. The results showed that the conversion of FAME using Tiwari’s method was 1.7-fold higher than Berchmans’s method. Purification of FAME using solvent fractionation resulted that the best CFAME/acetone ratio was 1. Yield decreased 1.6-fold at CFAME/acetone ratio 4. Purity decreased 8.74% with an increase in CFAME/acetone ratio 1 to 5. Purification factor decreased 2-fold at CFAME/acetone 1 to 3. Recovery decreased 1.3-fold at CFAME/acetone ratio 1 to 4. The impurities which were separated from FAME were mono-, di-, triglycerides, and free fatty acids and the major component of impurities was triglycerides (>59%). The results indicated that solvent fractionation could be used as an alternative method for purifying FAME and further study to optimize this method was needed.


2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Kwang Seo Park ◽  
Yun Ju Kim ◽  
Eun Kyung Choe

To implement EU REACH- (Registration, Evaluation, and Authorization of Chemicals-) like chemical legislations in various countries of which the purpose is human and environment safety, the first step is substance identification followed by the hazard and risk assessments. Although both structural and composition identifications are required, the latter can more importantly result in the essential data to fill out the required substance information such as purity and concentrations of constituents, as well as impurities. With fatty acid zinc salts (FAZSs) as an exemplary industrial chemical of which chromatographic and nuclear magnetic resonance (NMR) analyses were impossible due to their insolubility in water and any organic solvents, the composition characterization was tried by preparing their fatty acid methyl esters (FAMEs) using the conc. HCl/methanol/toluene method. This acid-catalyzed methyl esterification was optimized with zinc stearate as a surrogate substance. Gas chromatography-mass spectrometry (GC-MS) and NMR analyses on methyl-esterified products revealed that the optimum conditions were at 90°C for 10 min or 45°C for 30 min with two equivalent HCl as well as at 45°C for 10 min with five equivalent HCl. Almost all zinc stearates were converted into the corresponding fatty acids with 97–99% conversion rates. Free fatty acids (FFAs) were detected in extracted ion chromatograms of pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) in the methyl-esterified products with incomplete conversions of 73∼79%. The optimized conc. HCl/methanol/toluene method of direct one-step reaction from FAZSs was compared with the two-step NaOH saponification/BF3-methanol method after acidic hydrolysis of FAZSs. The mechanism of fatty acid zinc salts into free fatty acids and fatty acid methyl esters was suggested with the evidence of the formation of Zn(OH)2.


2016 ◽  
Vol 8 (2) ◽  
pp. 92
Author(s):  
Hamidou SENOU ◽  
Cai X. ZHENG ◽  
Gabriel SAMAKE ◽  
Mamadou B. TRAORE ◽  
Fousseni FOLEGA ◽  
...  

<p class="1Body">The methyl esters of fatty acids composition of the oil from <em>jatropha curcas</em> seeds were analyzed by gas chromatography-mass spectrometer GC-MS. Fourteen components were found to be representative with 99.52% of the total content of seed oils. The main constituents were unsaturated fatty acids (71.93%) and saturated fatty acids (27.59%). For the saturated fatty acids composition such as palmitic and stearic acid, the rate was 15.80% and 10.79%, respectively. Linoleic acid (39.58%) and oleic acid (30.41%) were obtained in highest concentration among the unsaturated fatty acids identified in the seeds oil of <em>Jatropha curcas</em> from Guizhou. This value also justifies the fluidity of the oil at room temperature. A high percentage of polyunsaturated fatty acids (39.58%) and a slightly lower rate of monounsaturated fatty acids (32.35%) were also observed. The seed oils profile of Guizhou <em>Jatropha curcas</em> presents the desirable fatty acid C14 to C18 and interesting features for the biodiesel production.</p>


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