Transesterification Procedure Research Articles

New bio-based monomers: tuneable polyester properties using branched diols from biomass.

A family of monomers, including 2,5-hexandiol, 2,7-octandiol, 2,5-furandicarboxylic acid (FDCA), terephthalic acid (TA), and branched-chain adipic and pimelic acid derivatives, all find a common derivation in the biomass-derived platform molecule 5-(chloromethyl)furfural (CMF). The diol monomers, previously little known to polymer chemistry, have been combined with FDCA and TA derivatives to produce a range of novel polyesters. It is shown that the use of secondary diols leads to polymers with higher glass transition temperatures (Tg) than those prepared from their primary diol equivalents. Two methods of polymerisation were investigated, the first employing activation of the aromatic diacids via the corresponding diacid chlorides and the second using a transesterification procedure. Longer chain diols were found to be more reactive than the shorter chain alternatives, generally giving rise to higher molecular weight polymers, an effect shown to be most pronounced when using the transesterification route. Finally, novel diesters with high degrees of branching in their hydrocarbon chains are introduced as potential monomers for possible low surface energy materials applications.

Total Fatty Acid Content Determination of Whole Microalgal Biomass Using In Situ Transesterification.

The aliphatic chains of fatty acids are the most prominent and potentially the highest value precursor constituents of algal biomass, and thus accurately quantifying the algal biomass total fatty acid content is a prerequisite for comparing algal strains, growth conditions, and processes. Direct, acid-catalyzed transesterification of whole microalgal biomass is a simple, effective, and widely used method to determine the fatty acid content in whole algal biomass. Such a direct transesterification procedure typically covers the following steps: first, solubilizing the lipids in the biomass matrix and then liberating the fatty acids to make these available for catalytic upgrading to fatty acid methyl esters (FAMEs), subsequent extraction into hexane, and then quantification by gas chromatography. The method we describe here requires less than 10mg of biomass per sample and is considered high-throughput and highly accurate.

Sleepy Extraction and Study of Biodiesel and Value Addition of Biomass Palletization

Biodiesel is principle wellspring of biodegradable, renewable and non-poisonous fuel for diesel motor operations. Biodiesel is gets from oils and fats of plants or creatures by transesterification process with alcohols and impetus. As option fuel like biodiesel and other strong fuel are extensive considerations amid the previous decades. Fundamental issue to the commercialization of biodiesel is crude materials cost. Utilization of consumable oils as biodiesel feedstock cost around 60-70% of crude material expense. No edible, cheap, poor quality with high free unsaturated fat rice wheat oil as crude material, persistent transesterification procedure and recuperation and decontamination of bioactive mixes from biodiesel by-item are essential alternatives to be considered to bring down the expense of biodiesel. The corrosive catalyzed or lipase catalyzed transesterification are the two critical reasonable strategies to deliver biodiesel from high unsaturated fat rice wheat oil. The procedure for the generation of biodiesel from rice wheat oil and other oils containing diverse Free Fatty Acid (FFA) substance and cleaning and disconnection of bioactive mixes from biodiesel deposit are as of now under scrutiny in this establishment.

Fluorescent Covalently Cross-Linked Cellulose Networks via Light-Induced Ligation.

A facile light-induced procedure for the covalent cross-linking of cellulose at ambient conditions employing the nitrile imine mediated tetrazole-ene cycloaddition (NITEC) reaction is presented. Cellulose-tetrazoles with 2 degrees of substitution (0.14 and 0.23) were synthesized in a solution-based transesterification procedure in an ionic liquid. Two bismaleimides with either a trioxatridecane or a dithiodipropionyl backbone were used as cross-linkers to form fluorescent, covalently cross-linked cellulose networks and films, which were characterized by UV/vis spectroscopy, fluorescence spectroscopy, DSC, and TGA. The films showed a broad emission band from 500-700 nm and were thermally stable up to 200 °C. Using the bismaleimide with a disulfide moiety as the cross-linker, reductive degradation of the films can be induced. Finally, cellulose-tetrazole was cross-linked in a spatially resolved fashion, providing a strategy for the shaping of films based on renewable resources.

Rapid transesterification of micro-amount of lipids from microalgae via a micro-mixer reactor.

BackgroundFatty acid composition is an important physiological parameter of microalgae, which is taken as the third generation alternative resource of biodiesel. To boost microalgal research and applications, a convenient, rapid, and acid-catalyzed transesterification procedure that satisfies the demand for the analysis of the fatty acid composition of lipids with micro-scale samples in the high-throughput screening of microalgal strains is needed, along with the evaluation of the physiological status of microalgae in response to nutrient stress.ResultsThe reaction conditions of transesterification via a micro-mixer reactor were optimized as follows: 90 °C reaction temperature, 20 min reaction time, 6:1 volume ratio of H2SO4-methanol to lipid-in-hexane, and a Y-type micro-mixer with a 20-m-long extended loop that has a 0.3 mm diameter. The minimum amount of sample was decreased to 30 µg lipids. The new approach was successfully applied to the fatty acid composition analysis of soybean oil and microalgal lipids. Definitely, it could be applied to acyl related oils from different sources.ConclusionHere, we have developed a simple and rapid method for the analysis of the fatty acid composition of lipids. The new method requires less than 20 min for transesterification and a minimum of only 30 µg lipid sample. Furthermore, a high-throughput process can be easily realized by numbering up the micro-mixer reactors. The micro-mixer reactor has great potential for applications not only in large-scale biodiesel production but also for the micro-scale analysis of microalgae fatty acid compositions.

Optimisation of enzymatic transesterification of linseed oil and pork lard mixture with ethanol using response surface methodology

Transesterification of linseed oil and pork lard mixture with ethanol was studied by applying a biotechnological method. The effectiveness of 16 lipases was evaluated, and the most effective lipase, Lipolase 100 L (EX), was selected for reaction condition optimisation by response surface methodology based on a Box-Behnken design. The influence of the main process parameters was evaluated, including the reaction temperature, ethanol to triglyceride molar ratio, lipase amount, and reaction time on transesterification yield. The optimal reaction conditions were found as follows: reaction temperature of 32.79 °C, ethanol to oil molar ratio of 5.99, lipase concentration of 6.39%, and reaction time of 7.95 h, with an expected transesterification yield of 52.2%. Optimised enzymatic pork fat and linseed oil mixture transesterification with ethanol was less effective compared with the chemical transesterifications described elsewhere; therefore, the step-wise transesterification procedure should be applied by adding ethanol and percent preparation in the reaction mixture after glycerol phase separation.

Yucca aloifolia oil methyl esters

Yucca aloifolia Linn (Y. aloifolia) is a drought-resistant arid land plant that grows in most soil types. In this work, Y. aloifolia seed oil (YAO) was evaluated for the first time as a potential biodiesel feedstock, which contains 16.23% oil (w/w) whereas the acidity of the oil was 11%. Two step processes i.e. acid-catalyzed esterification to reduce the acid value of YAO and then standard base-catalyzed transesterification procedure were used to synthesis the Y. aloifolia methyl esters (Yame) at optimization conditions. YAO has a high content of linoleic acid (70.77 %) followed by oleic acid (12%), and palmitic acid (8.59%). The fuel properties of biodiesel derived from YAO including density, iodine value, kinematic viscosity, cetane number, flash point, pour point, cloud point, and gross heating value were evaluated and compared with the limits of ASTM D6751 standards. The comparison showed that the biodiesel obtained from Y. aloifolia oil could be used as an alternative fuel for diesel engines.

Evaluation of an enantioselective synthesis of 6-chloro-3,4-dihydro-2H-1,2-benzothiazine-3-carboxylic acid 1,1-dioxide and its derivatives

Step-by-step evaluation of an enantioselective synthesis of (S)- and (R)-ethyl 3,4-dihydro-2H-1,2-benzothiazine-3-carboxylates is described, starting from (S)- and (R)-methyl 2-acetamido-3-(3-chlorophenyl)propanoates as a source of chirality. A one-pot procedure for transesterification and cleavage of the N-acetyl group was developed to prevent racemization during the hydrolysis of the methyl ester group. It was demonstrated that the synthesized benzothiazines might serve as useful building blocks for enantioselective synthesis of pharmacologically active compounds.

Synthesis and antioxidant activity of nitrohydroxytyrosol and its acyl derivatives.

A series of nitroderivatives has been synthesized from hydroxytyrosol, the natural olive oil phenol, to increase the assortment of compounds with putative effects against Parkinson's disease. Nitrohydroxytyrosyl esters were obtained from nitrohydroxytyrosol using a chemoselective one-step, high-yield, transesterification procedure. The antioxidant activity of these new series of nitrocatechols was evaluated using FRAP, ABTS, and ORAC assays and compared to that of free hydroxytyrosol. The nitro functional group induced a significant increase in the antioxidant activity of nitrohydroxytyrosol compared to hydroxytyrosol. Regarding nitroester derivatives, variable antioxidant activity was observed depending on the acyl side-chain length; shorter chains maintained or even enhanced the antioxidant activity compared to nitrohydroxytyrosol, decreasing the activity with longer side chains in keeping with their lipophilic nature. Therefore, it may be concluded that nitroester derivatives of hydroxytyrosol, which may be obtained by a simple, high-yield reaction, have elevated antioxidant activity and thus present potential bioactivity.

Annona diversifolia seed oil as a promising non-edible feedstock for biodiesel production

In this work, Annona diversifolia seed oil (ADO) is evaluated for the first time as potential biodiesel feedstock. ADO was found to contain 21% oil (w/w) after extraction, and the low acid value of the oil was 0.666mg KOH/g. Therefore, ADO was considered suitable for alkali-catalyzed transesterification. A. diversifolia biodiesel (ADB) was obtained from ADO by a standard transesterification procedure with methanol, and alkali catalyst. ADO has a high content of oleic acid (70%) and palmitic acid (16%). The fuel properties of the oil and biodiesel made from ADO were evaluated, including density, iodine value, kinematic viscosity, cetane number, flash point, pour point, cloud point, acid value, and gross heating value. The ADB properties were compared with several limits prescribed in the ASTM D6751 standards. The comparison shows that the biodiesel obtained from A. diversifolia oil could be used as an alternative fuel in conventional diesel engines.

ChemInform Abstract: Solvent‐Free Transesterification in a Ball‐Mill over Alumina Surface.

ChemInformVolume 43, Issue 47 Preparative Organic Chemistry ChemInform Abstract: Solvent-Free Transesterification in a Ball-Mill over Alumina Surface. Tanmay Chatterjee, Tanmay Chatterjee Dep. Org. Chem., Indian Assoc. Cultiv. Sci., Kolkata 700 032, IndiaSearch for more papers by this authorDebasree Saha, Debasree Saha Dep. Org. Chem., Indian Assoc. Cultiv. Sci., Kolkata 700 032, IndiaSearch for more papers by this authorBrindaban C. Ranu, Brindaban C. Ranu Dep. Org. Chem., Indian Assoc. Cultiv. Sci., Kolkata 700 032, IndiaSearch for more papers by this author Tanmay Chatterjee, Tanmay Chatterjee Dep. Org. Chem., Indian Assoc. Cultiv. Sci., Kolkata 700 032, IndiaSearch for more papers by this authorDebasree Saha, Debasree Saha Dep. Org. Chem., Indian Assoc. Cultiv. Sci., Kolkata 700 032, IndiaSearch for more papers by this authorBrindaban C. Ranu, Brindaban C. Ranu Dep. Org. Chem., Indian Assoc. Cultiv. Sci., Kolkata 700 032, IndiaSearch for more papers by this author First published: 30 October 2012 https://doi.org/10.1002/chin.201247044Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume43, Issue47November 20, 2012 RelatedInformation

Solvent-free transesterification in a ball-mill over alumina surface

An efficient procedure for transesterification has been developed in a ball-mill in the absence of any solvent, acid/base or metal catalyst. A variety of methyl, ethyl, allyl esters have been transesterified to higher benzyl and other esters in high yields by this procedure.

Accurate and reliable quantification of total microalgal fuel potential as fatty acid methyl esters by in situ transesterification

In the context of algal biofuels, lipids, or better aliphatic chains of the fatty acids, are perhaps the most important constituents of algal biomass. Accurate quantification of lipids and their respective fuel yield is crucial for comparison of algal strains and growth conditions and for process monitoring. As an alternative to traditional solvent-based lipid extraction procedures, we have developed a robust whole-biomass in situ transesterification procedure for quantification of algal lipids (as fatty acid methyl esters, FAMEs) that (a) can be carried out on a small scale (using 4–7 mg of biomass), (b) is applicable to a range of different species, (c) consists of a single-step reaction, (d) is robust over a range of different temperature and time combinations, and (e) tolerant to at least 50% water in the biomass. Unlike gravimetric lipid quantification, which can over- or underestimate the lipid content, whole biomass transesterification reflects the true potential fuel yield of algal biomass. We report here on the comparison of the yield of FAMEs by using different catalysts and catalyst combinations, with the acid catalyst HCl providing a consistently high level of conversion of fatty acids with a precision of 1.9% relative standard deviation. We investigate the influence of reaction time, temperature, and biomass water content on the measured FAME content and profile for 4 different samples of algae (replete and deplete Chlorella vulgaris, replete Phaeodactylum tricornutum, and replete Nannochloropsis sp.). We conclude by demonstrating a full mass balance closure of all fatty acids around a traditional lipid extraction process. FigureAccurate quantification of different types of lipids in algal biomass using a comprehensive study of reaction parameters. Electronic supplementary materialThe online version of this article (doi:10.1007/s00216-012-5814-0) contains supplementary material, which is available to authorized users.

Comparison of Transesterification Methods for Fatty Acid Analysis in Higher Fungi: Application to Mushrooms

This study evaluated the effectiveness of two commonly used transesterification methods for the preparation of fatty acid methyl esters (FAMEs) for gas chromatographic analysis. A combination of base followed by acid catalysis [potassium hydroxide/sulfuric acid/methanol (KOH–H2SO4–MeOH)] was compared to an acid-only catalyst [methanolic–boron trifluoride (BF3–MeOH)] for the quantification of the fatty acid content in mushrooms after preextraction of total lipids with chloroform/methanol (2:1 v/v). The mushrooms studied were commonly cultivated species, Agaricus bisporus (brown) and A. bisporus (white), and three wild medicinal mushrooms, turkey tail (Trametes versicolor), artist conk (Ganoderma applanatum), and tinder polypore (Fomes fomentarius). The major fatty acids identified were palmitic (C16:0), stearic (C18:0), oleic (C18:1), and linoleic acid (18:2n6) which constituted 80% to 90% of the total amount. Variation due to the FAME preparation methods was observed in both minor and major fatty acids. Another major observation made between the two methods was the total number of individual fatty acids (FAs) methylated. The base and acid transesterification procedure resulted in the identification of 42 FAMEs, whereas with the acid 38 FAMEs were observed. Therefore, the research recommends the use of a base–acid combination for preparation of FAMEs in mushroom lipids.

Production of biodiesel from pentaclethra macrophylla seed oil

In the present work, the potentials of pentaclethra macrophylla (Africa oil bean) seed oil (PMSO) are evaluated for the first time as a feedstock for biodiesel. Methyl (PMFAME) and ethyl (PMFAEE) esters of PMSO were produced by standard transesterification procedure using potassium hydroxide (KOH) as catalyst and their qualities determined. Gas chromatography mass spectrometry (GCMS) runs of the biodiesels revealed that the linoleic acid (unsaturated fatty acid) of the methyl esters (55.68%) and ethyl esters (33.45%) of PMSO dominate the fatty acid profile. The viscosity, flash point, cloud point, pour point and acid number of PMFAME and PMFAEE were found to be 4.08 mm 2 /s and 4.16 mm 2 /s; 196°C and 198°C; –5°C and 2°C; 0°C and 1°C; 0.50 mgKOH/g and 0.20 mgKOH/g. The calculated cetane number of 36.72 and higher heating value of 40.47 KJ/g were obtained for both PMFAME and PMFAEE. These together with other fuel parameters were compared with those of soy oil fatty acid methyl esters (SFAME) and ethyl esters (SFAEE), diesel – fuel (D 2 ), ASTM and European (EN 14214) standards. The results obtained indicate that PMSO appears to be a potential feedstock for biodiesel production.

Transesterification double step process modification for ethyl ester biodiesel production from vegetable and waste oils

In this study, the transesterification double step process (TDSP) was modified to enable the usage of ethanol as a transesterification agent in the production of biodiesel from vegetable and waste oils. The TDSP comprises a two-step transesterification procedure, which is initiated by a homogeneous basic catalysis step and followed by an acidic catalysis step. To optimize the transesterification parameters, different reaction mixtures and conditions were tested. Compared with methanol transesterification, larger ethanol and catalyst amounts as well as higher reaction times and temperatures were required. However, the results were consistent with those usually reported for ethanol transesterification. The obtained biodiesels (i.e., fatty acid ethyl esters (FAEEs)) were analyzed by standard physico-chemical techniques in addition to 1H NMR, 13C NMR and FTIR spectroscopies, indicating high quality and purity biodiesel products. The obtained conversions were evaluated by 1H NMR spectroscopy. For the optimized process, the triglyceride conversion to biodiesel was ⩾97% for all oils used. The overall process yields are considerably high when compared to the single basic catalysis yields.

The use of a modified TDSP for biodiesel production from soybean, linseed and waste cooking oil

In this study, the Transesterification Double Step Process (TDSP) for the production of biodiesel from vegetable oil was modified to yield a shorter reaction time and products with improved quality. TDSP consists in a two step transesterification procedure which starts with a basic catalysis, followed by an acidic catalysis. The process modifications included a reduction in the concentration of catalysts, a reduction in the reaction time of the first step and the direct mixing of methanol/acid solution, without cooling the system between the first and second step. A comparison between washed and unwashed biodiesel demonstrates that the final washing and drying procedure is necessary for satisfactory results. The products were analyzed by 1H-NMR and nineteen different biodiesel analyses specific for international quality certification. The modified procedure resulted in a high conversion index (97% for waste cooking oil and soybean oil and 98% for linseed oil) and high yield (87 ± 5% for waste cooking oil, 92 ± 3% for soybean and 93 ± 3% for linseed oil). The biodiesel produced by the modified TDSP met ASTM, EN ISO and ABNT standards before the addition of stabilizer.

Direct analysis of fatty acid profile from milk by thermochemolysis–gas chromatography–mass spectrometry

The fatty acid composition of milk is of considerable interest due to their nutritional and functional properties. Although rapid milk fat separation and transesterification procedures have been developed, the overall procedure remains time consuming, specially, for the analysis of a large number of samples. In this work, a fast and simple method for direct profiling of fatty acids from milk using thermochemolysis has been developed. This method has the capability of directly analyse fatty acids from one drop of milk without fat extraction or cleanup. Our approach for thermochemolysis is based on thermal desorption integrated with a cold trap inlet. The optimized method does not present isomerisation/degradation of polyunsaturated fatty acid and shows milk fatty acid profiles comparable to the conventional method based on fat extraction and alkaline transesterification. Overall, this method has demonstrated significant potential for high throughput analysis of fatty acids in milk.

Synthesis of solamin type mono-THF acetogenins using cross-metathesis

The total synthesis of mono-THF acetogenins, cis-solamin A and B, and reticulatacin, was accomplished starting with muricatacin. The backbone of the mono-THF acetogenins was constructed by olefin cross-metathesis between the tetrahydrofuran moiety and γ-lactone moiety. An enzymatic kinetic transesterification procedure was successfully applied to the synthesis of an optically pure γ-lactone moiety. Notably, cis-THF compounds were obtained without using protective groups.

ChemInform Abstract: A Simple and Efficient Procedure for Transesterification Catalyzed by Indium Triiodide.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.