Artykuły w czasopismach: „Transesterification”

1

Otera, Junzo. "Transesterification". Chemical Reviews 93, nr 4 (czerwiec 1993): 1449–70. http://dx.doi.org/10.1021/cr00020a004.

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Masumizu, Tatsuya, Koohei Nozawa, Ken-ichi Kawai i Shoichi Nakajima. "Electrocatalytic transesterification". Tetrahedron Letters 27, nr 1 (styczeń 1986): 55–56. http://dx.doi.org/10.1016/s0040-4039(00)83938-6.

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Whitney, M. B., B. W. Hess, J. E. Kaltenbach, H. J. Harlow i D. C. Rule. "Direct transesterification of lipids from feedstuffs and ruminal bacteria". Canadian Journal of Animal Science 79, nr 2 (1.06.1999): 247–49. http://dx.doi.org/10.4141/a98-110.

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Direct transesterification of feedstuffs, browse plants, and ruminal bacteria was compared to transesterification of solvent extracted lipids. Weight percentages were of similar magnitude between procedures. Direct transesterification often produced higher concentrations of fatty acids. Results indicate that direct transesterification is an acceptable method for analysis of total fatty acids. Key words: Transesterification, lipids, feedstuffs, bacteria

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Wicakso, Doni Rahmat, Anniy Nurin Najma i Diah Ayu Retnowati. "CRUDE BIODIESEL SYNTHESIS FROM RUBBER SEED OIL". Konversi 7, nr 1 (25.11.2019): 21. http://dx.doi.org/10.20527/k.v7i1.4872.

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Abstract-Biodiesel is a diesel engine fuel made from oil containing triglycerides as well as rubber seed oil. This research aims to study how the extraction process of rubber seed oil, to know the effect of crude biodiesel manufacturing process by transesterification and esterification-transesterification and the addition of different catalysts on the transesterification process of crude biodiesel produced. Esterification process use H2SO4 catalyst and transesterification process use KOH and NaOH catalyst. The process of making crude biodiesel done by transesterification and can also by the merging of esterification-transesterification process. Based on this research, yield of crude biodiesel produced by transesterfication and esterification-transesterification by using NaOH catalyst is 38% and 75,6%, while yielded by KOH catalyst is 22,5% and 80%. While the acid number obtained from the transesterification process and esterification-transesterification using KOH catalyst is the same that is 1.33 and for the NaOH catalyst is 1,83 and 1,68. Saponification number obtained from both processes using KOH catalysts were 24,68 and 26,37 and for NaOH catalysts were 18,51 and 20,20. Keywords: Rubber seed oil, crude biodiesel, acid number, saponification number.

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Prošková, A., Z. Kopicová, J. Kučera i L. Škarková. "Acid catalysed transesterification of animal waste fat". Research in Agricultural Engineering 55, No. 1 (11.02.2009): 24–28. http://dx.doi.org/10.17221/20/2008-rae.

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Rendering plant fat (RPF) was collected and different conditions were used for transesterification. The course of transesterification of RPF was compared with that of transesterification of lard under the same conditions. Significant diffe-rences were found between transesterification of RPF and that of lard. Optimum methanol excess for lard transesterification was found to be 30-fold, for RPF 10-fold, optimum sulfuric acid concentration was 1% for lard, 2.5% for RPF. Optimum temperature as well as optimum reaction time were similar in both cases. The fatty acid composition is similar but not identical in both fats. RPF contains a higher amount of free acid which could be the reason for the differences observed.

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Bérešová, Miroslava, András Peller i Michal Horňáček. "Biodiesel preparation from Camelina sativa oil by homogeneous and heterogeneous transesterification". E3S Web of Conferences 545 (2024): 03001. http://dx.doi.org/10.1051/e3sconf/202454503001.

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Biodiesel is one of the possible alternatives to diesel fuel to address the issue of fossil fuels and their impact on the environment. Substituting homogeneous transesterification with heterogeneous offers advantages such as improved catalyst and product separation, catalyst regeneration, and avoidance of saponification during the reaction. To compare homogeneous and heterogeneous transesterification, the commonly used homogenous catalyst NaOH was tested. As a heterogeneous catalyst, a mixed oxide prepared from hydrotalcite with added nickel in its structure was used. By employing suitable conditions, it is possible to achieve biodiesel through heterogeneous transesterification with a comparable FAME (Fatty acid methyl ester) content to homogeneous transesterification, meeting the standardized value of over 96.7 wt.%. Implementing a two-step heterogeneous transesterification process decreases the reaction time needed to reach the desired FAME quantity. Furthermore, following heterogeneous transesterification, glycerol as a valuable secondary product showed visibly higher purity.

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Watcharakitti, Jidapa, Jaturavit Nimnuan, Kuakarun Krusong, Suwat Nanan i Siwaporn Meejoo Smith. "Insight into the Molecular Weight of Hydrophobic Starch Laurate-Based Adhesives for Paper". Polymers 15, nr 7 (31.03.2023): 1754. http://dx.doi.org/10.3390/polym15071754.

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Instead of using finite petroleum-based resources and harmful additives, starch can be used as a biodegradable, low-cost, and non-toxic ingredient for green adhesives. This work employs K3PO4 catalyzed transesterifications of cassava starch and methyl laurate at varying reaction times (1–10 h), resulting in the enhanced hydrophobicity of starch laurates. At longer reaction times, starch laurates having higher degrees of substitution (DS) were obtained. While starch laurates are the major products of transesterification, relatively low-molecular-weight byproducts (1%) were detected and could be hydrolyzed starches based on gel permeation chromatography results. Contact angle measurements confirmed the relatively high hydrophobicity of the modified starches compared with that of native starch. The modified starches were then employed to prepare water-based adhesives on paper (without any additional additives). Notably, the shear strength of the esterified starch adhesives appears to be independent of the DS of esterified samples, hence the transesterification reaction times. Additionally, the shear strength of water-based adhesives (0.67–0.73 MPa) for bonding to paper substrates is superior to that of two other commercially available glues by a factor of 10 to 80 percent.

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RITTER, STEVE. "FLUOROUS BIPHASIC TRANSESTERIFICATION". Chemical & Engineering News 79, nr 40 (październik 2001): 15. http://dx.doi.org/10.1021/cen-v079n040.p015.

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OTERA, J. "ChemInform Abstract: Transesterification". ChemInform 24, nr 39 (20.08.2010): no. http://dx.doi.org/10.1002/chin.199339347.

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Golmakani, M. T., M. Niakousari, A. Peykar i T. Safaeipour. "Microwave-assisted transesterification of sour cherry kernel oil for biodiesel production: comparison with ultrasonic bath-, ultrasonic probe-, and ohmic-assisted transesterification methods". Grasas y Aceites 75, nr 1 (10.04.2024): e545. http://dx.doi.org/10.3989/gya.0429231.

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In this study, sour cherry kernel oil was converted to biodiesel by microwave-assisted transesterification. Evaluations were made of several variables, namely, reaction time (1, 2, 3, 4, and 5 min), microwave power (100, 200, 300, 400, and 500 W), methanol/oil mole ratio (3, 6, 9, 12, and 15), and catalyst (KOH) concentration (0.3%, 0.6%, 0.9%, 1.2%, and 1.5%). The efficiency of fatty acid methyl esters increased in response to lengthier reaction times, greater microwave power, higher methanol/oil mole ratio, and higher catalyst concentrations up to the optimal level. The optimal reaction conditions for microwave-assisted transesterification were 300 W microwave power, 1.2% catalyst concentration, a methanol/oil mole ratio of 1:2, and a reaction time of 4 min. Microwave-assisted transesterification was more effective than ohmic-, magnetic stirrer-, ultrasonic probe-, and ultrasonic bath-assisted transesterification methods. In conclusion, microwave-assisted transesterification can be suggested as a fast, efficient, and economical method compared to other transesterification methods.

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Pramana, Yanatra budi. "C. Biodiesel Dari Minyak Biji Nyamplung Melalui Proses Transesterifikasi Dengan Reaktor Sistem Aliran Berkelanjutan". Jurnal Teknik Industri dan Kimia 2, nr 1 (3.06.2019): 19–26. http://dx.doi.org/10.54980/jtik.v2i1.80.

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This study aims to study the effect of temperature, flow velocity in the reactor and product flow velocity on FAME yield in the transesterification process of nyamplung seed oil into biodiesel in packed bed columns. As a whole the process involved includes degumming, acid catalyzed esterification and alkaline catalyzed transesterification. The transesterification process is carried out in a packed bed column. In the transesterification process, the fixed variable is the molar ratio of methanol to oil and the amount of NaOH catalyst to oil. While the independent variables are temperature, flow velocity in the reactor and the transesterification product flow rate and the response variable is (percentage)% FAME in the product. To obtain% FAME, product samples were analyzed using GC with internal standard methods.

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Vakros, John. "Biochars and Their Use as Transesterification Catalysts for Biodiesel Production: A Short Review". Catalysts 8, nr 11 (20.11.2018): 562. http://dx.doi.org/10.3390/catal8110562.

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Biodiesel can be a significant alternative for diesel. Usually, it is produced through transesterification with a base catalyst. Using heterogeneous catalysts for transesterification, the process can be more efficient. Among the possible catalysts that can be used, biochars combine high performance for transesterification and valorization of waste biomass. Biochars are cheap materials, and are easy to activate through chemical treatment with acid or base solutions. In this short review, the application of biochar as solid heterogeneous catalysts for transesterification of lipids to produce biodiesel is discussed.

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Gumbytė, Milda, Violeta Makareviciene i Egle Sendzikiene. "Enzymatic Transesterification of Atlantic Salmon (Salmo salar) Oil with Isoamyl Alcohol". Materials 16, nr 3 (30.01.2023): 1185. http://dx.doi.org/10.3390/ma16031185.

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In this experimental study, biodiesel was synthesized from the salmon oil using the Lipozyme®RM IM (Bagsværd, Denmark) as a biocatalyst. Isoamyl alcohol was used as an acyl acceptor in the transesterification process. The aim of this study is to select the best process conditions, aiming to obtain the highest transesterification degree that meets the requirements of the EN 14214 standard. Response surface methodology (RSM) was used for statistical analysis and optimization of process parameters. A four-factor experimental design was modelled by central compositional design (CCD) to investigate the effects of biocatalyst concentration, isoamyl alcohol-to-oil molar ratio, temperature, and duration on transesterification degree. It was determined that the optimal parameters for biodiesel synthesis were the following: an enzyme concentration of 11% (wt. of oil mass); a process temperature of 45 °C; a process duration of 4 h; and an alcohol-to-oil molar ratio of 6:1. The transesterification degree of biodiesel reached 87.23%. The stepwise addition of isoamyl alcohol during the transesterification process further increased the degree of transesterification to 96.5%.

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Stamenkovic, Olivera, Miodrag Lazic, Vlada Veljkovic i Dejan Skala. "Biodiesel production by enzyme-catalyzed transesterification". Chemical Industry 59, nr 3-4 (2005): 49–59. http://dx.doi.org/10.2298/hemind0504049s.

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The principles and kinetics of biodiesel production from vegetable oils using lipase-catalyzed transesterification are reviewed. The most important operating factors affecting the reaction and the yield of alkyl esters, such as: the type and form of lipase, the type of alcohol, the presence of organic solvents, the content of water in the oil, temperature and the presence of glycerol are discussed. In order to estimate the prospects of lipase-catalyzed transesterification for industrial application, the factors which influence the kinetics of chemically-catalysed transesterification are also considered. The advantages of lipase-catalyzed transesterification compared to the chemically-catalysed reaction, are pointed out. The cost of down-processing and ecological problems are significantly reduced by applying lipases. It was also emphasized that lipase-catalysed transesterification should be greatly improved in order to make it commercially applicable. The further optimization of lipase-catalyzed transesterification should include studies on the development of new reactor systems with immobilized biocatalysts and the addition of alcohol in several portions, and the use of extra cellular lipases tolerant to organic solvents, intracellular lipases (i.e. whole microbial cells) and genetically-modified microorganisms ("intelligent" yeasts).

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Rezki, Rezki, Rustam Musta i Aceng Haetami. "Minyak Biji Nyamplung (Calophyllum inophyllum) Dengan Etanol". Indo. J. Chem. Res. 4, nr 2 (31.01.2017): 406–12. http://dx.doi.org/10.30598//ijcr.2017.4-rez.

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A study has been conducted on the transesterification of Calophyllum innophyllum seed oil with ethanol. The purpose of this research is to determine the comparison of concentration of phosphoric acid used to remove the gum on the oil, ester content is produced in the process of transesterification with ethanol, the ester yield obtained after the final stage of the transesterification process, the viscosity of the biodiesel produced, moisture content of biodiesel is produced, and density of biodiesel was produced. This research is taken based on consideration production biodiesel by direct transesterification process. Based on research result of good phosphoric acid concentration used to remove oil gum is 85%, volume of biodiesel produced at transesterification equal to 150 mL with yield 80,89%, biodiesel quality parameter measured that viscosity = 0,05 mm2 / s not fulfill Indonesian National Standart (INS), moisture content = 0.045 meets the INS and the density = 0.881 g / cm3 meets the INS

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Hazmi, Alia Tasnim, Farah B. Ahmad, Ahdyat Zain Athoillah i Ahmad Tariq Jameel. "Comparison of Ex-Situ and In-Situ Transesterification for the Production of Microbial Biodiesel". Bulletin of Chemical Reaction Engineering & Catalysis 16, nr 4 (2.08.2021): 733–43. http://dx.doi.org/10.9767/bcrec.16.4.11044.733-743.

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Microbial biodiesel is converted from microbial lipids via transesterification process. Most microbial biodiesel studies are focusing on the use of microalgal lipids as feedstock. Apart from using microalgae for lipid biosynthesis, lipids can also be extracted from other oleaginous microorganisms like fungi and yeast. However, there are gaps in the studies of lipid production from filamentous fungi, especially in-situ transesterification process. The aim of this project is to compare in-situ with the ex-situ transesterification of fungal biomass from Aspergillus oryzae. In ex-situ transesterification, two methods of lipid extraction, the Soxhlet extraction and the Bligh and Dyer extraction, were performed. For in-situ transesterification, two methods using different catalysts were investigated. Base-catalyzed in-situ transesterification of fungal biomass resulted on the highest Fatty Acid Methyl Esters (FAME) yield. The base-catalyzed in-situ transesterification was further optimized via Central Composite Design (CCD) of Response Surface Methodology (RSM). The parameters investigated were the catalyst loading, methanol to biomass ratio and reaction time. The optimization showed that the highest FAME yield was at 25.1% (w/w) with 10 minutes reaction time, 5% catalyst and 360:1 of the ratio of the methanol to biomass. Based on Analysis of Variance (ANOVA), the model was found to be significant according to the value of “Prob >F” of 0.0028. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

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Pranowo, Deni, i M. Muchalal. "ANALYSIS OF FREE FATTY ACID ON SOYBEAN OIL USING GAS CHROMATOGRAPHY – MASS SPECTROSCOPY". Indonesian Journal of Chemistry 4, nr 1 (9.06.2010): 62–67. http://dx.doi.org/10.22146/ijc.21875.

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Research on transesterification of soybean oil with sodium methoxide as the catalyst in methanol has been conducted. Yields of transesterification reaction were analyzed by gas chromatography-mass spectroscopy (GC-MS). GC-MS spectrum showed that mehtyl palmitic, methyl stearic, methyl oleic and methyl linoleic were produced from the reaction. The reaction was done for 90 minutes and gave convertion of 84.53% (b/b). Keywords: transesterification, soybean oil

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Prošková, A., J. Kučera, Z. Kopicová i L. Škarková. "Comparison of three methods for rendering plant fat transesterification". Research in Agricultural Engineering 59, No. 2 (31.05.2013): 51–55. http://dx.doi.org/10.17221/19/2011-rae.

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Three most frequently used methods for fat transesterification were compared using rendering plant fat (RPF) as model. Acid-catalysed transesterification was found to be the most effective (conversion 90%) at optimum conditions (fat: methanol ratio 1:10, sulphuric acid amount of 2% v/v, temperature 95°C). Base-catalysed transesterification of RPF on the other hand, results in much lower conversion (45%) at optimum conditions (fat:methanol ratio 1:20, NaOH amount 8% w/v, optimum temperature 95°C). The difference is done (among others) by the fact that RPF has high concentration of free acid (high acidity number) compared with the fats usually used for transesterification and that free acids are not esterified in alkaline media. Enzyme-(lipase) catalysed reaction could lead to partial esterification of free fatty acids, but with much lower reaction velocity. This fact leads to higher conversion in the case of enzyme-catalysed transesterification of RPF compared with base-catalysed reaction; nevertheless, even in this case the conversion is much lower in comparison with acid-catalysed reaction. The optimum conversion in enzyme-catalysed reaction was 55%.  

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Ruiz-Domínguez, Mari Carmen, Constanza Toledo, Daniel Órdenes, Carlos Vílchez, Paula Ardiles, Jenifer Palma i Pedro Cerezal. "Variability of Omega-3/6 Fatty Acid Obtained Through Extraction-Transesterification Processes from Phaeodactylum tricornutum". Acta Chimica Slovenica 68, nr 3 (15.09.2021): 629–37. http://dx.doi.org/10.17344/acsi.2020.6621.

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The effect of direct transesterification methods on the omega-3/6 composition of extracts from Phaeodactylum tricornutum was studied. The aim of this work was to identify an extraction method which allowed to obtain the most suitable profile of fatty acids in terms of its potential benefits to health, particularly if further used in the food industry. Seven methods using acids, alkalis, and heterogeneous-catalysts, (namely methods from 1 to 7, abbreviated as M1-M7) were performed to determine α-linolenic (ALA), linoleic (LA), docosahexaenoic (DHA) and eicosapentaenoic (EPA) acids. The composition of fatty acids was in all cases characterized by the major abundance of palmitic (23.95–34.08%), palmitoleic (30.94–35.56%), oleic acids (3.00–7.41%), and EPA (0.5–6.45%). Unsaturated fatty acids extraction yield was higher with a two-step transesterification process (M6, 63.65%). The total fatty acid methyl ester content (FAME) obtained with acid-transesterification (M1) reached about 21% wt, and 60% w/w total lipids. ALA higher relative content (ALA/LA ratio) was obtained when a lipid pre-extraction step was performed prior to acid-catalysis (M4). The transesterification method based on alkali-catalyst (M3, KOH catalyst) led to obtain higher DHA relative contents (DHA/EPA ratio up to 0.11), although its FAME content was 3.75-fold lower than that obtained with acid-transesterification (M1). Overall, this study shows that direct transesterification with alkali-catalyst (M3) improves the determination of PUFA content from the diatom through a more efficient transesterification-based extraction process, and thus allow to assess the value of the biomass more accurately for application in the food industry.

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Akhmetshina, A. I., L. K. Karimova i R. Ya Deberdeev. "High-Performance Polyesters: Synthesis, Characterization, and Properties of Poly(P-Oxybenzoate)". Materials Science Forum 992 (maj 2020): 380–85. http://dx.doi.org/10.4028/www.scientific.net/msf.992.380.

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Poly (p-oxybenzoate) samples were synthesized via the esterification and the transesterification reactions. The structure of the obtained target products was investigated by IR spectroscopy and has revealed that these substances were oligomers. The transesterification method has facilitated the synthesis of higher molecular weight grades of the polymer. This resulted in enhanced thermal properties of polyester synthesized by transesterification (up to 340 °C). The other specimen has performed thermal stability up to 320 °C.

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Neag, Emilia, Zamfira Stupar, S. Andrada Maicaneanu i Cecilia Roman. "Advances in Biodiesel Production from Microalgae". Energies 16, nr 3 (19.01.2023): 1129. http://dx.doi.org/10.3390/en16031129.

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Biofuels, as a renewable, eco-friendly, and cost-effective energy source, can reduce the dependence on fossil fuels. The researchers considered different approaches for obtaining high biodiesel yields from microalgae biomass. This work aims to present an overview of the feasibility of microalgae use in biodiesel production. Therefore, biodiesel production from microalgae oil via the transesterification process was explained in detail. The application of non-catalytic transesterification and catalytic transesterification was reviewed. The achievements in the application of homogenous catalysts, heterogeneous catalysts, and enzymatic catalysts for microalgae oil transesterification were discussed. The present technologies for biodiesel production from microalgae need more improvements to increase their efficiencies and reduce costs. Therefore, future research should focus on the development of effective catalysts for biodiesel production from microalgae biomass.

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Nasir, N. F., W. R. W. Daud, S. K. Kamarudin i Z. Yaakob. "Methyl Esters Selectivity of Transesterification Reaction with Homogenous Alkaline Catalyst to Produce Biodiesel in Batch, Plug Flow, and Continuous Stirred Tank Reactors". International Journal of Chemical Engineering 2014 (2014): 1–13. http://dx.doi.org/10.1155/2014/931264.

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Selectivity concept is essential in establishing the best operating conditions for attaining maximum production of the desired product. For complex reaction such as biodiesel fuel synthesis, kinetic studies of transesterification reaction have revealed the mechanism of the reaction and rate constants. The objectives of this research are to develop the kinetic parameters for determination of methyl esters and glycerol selectivity, evaluate the significance of the reverse reaction in transesterification reaction, and examine the influence of reaction characteristics (reaction temperature, methanol to oil molar ratio, and the amount of catalyst) on selectivity. For this study, published reaction rate constants of transesterification reaction were used to develop mathematical expressions for selectivities. In order to examine the base case and reversible transesterification, two calculation schemes (Case 1 and Case 2) were established. An enhanced selectivity was found in the base case of transesterification reaction. The selectivity was greatly improved at optimum reaction temperature (60°C), molar ratio (9 : 1), catalyst concentration (1.5 wt.%), and low free fatty acid feedstock. Further research might explore the application of selectivity for specifying reactor configurations.

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Telussa, Ivon, Eirene G. Fransina i Kalsum Kalauw. "Synthesis of Methyl Ester from Microalgae Chlorella sp. TAD Using the In-Situ Transesterification Method". Jurnal Teknik Kimia dan Lingkungan 8, nr 1 (29.04.2024): 63–69. http://dx.doi.org/10.33795/jtkl.v8i1.3197.

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Synthesis of methyl ester from Chlorella sp. TAD microalgae was carried out using the in-situ transesterification method. This study aims to determine the methyl ester composition of Chlorella sp. TAD microalgae using the in-situ transesterification method. The in-situ transesterification method is a modified method that allows extraction and transesterification into methyl ester products in one process simultaneously. The in-situ transesterification process lasted 8 hours, followed by a distillation process to remove the n-hexane content and an oven for 2 hours to evaporate the remaining water. The results of the analysis using GC-MS to determine the chemical content of the methyl ester compound from Chlorella sp. TAD, showed the methyl ester composition of 7,10-hexadecanoic methyl ester, 8,11,14-docosatrienoic methyl ester, 9-hexadecanoic methyl ester, hexadecanoic methyl ester, heptadecanoic methyl ester, 10-octadecenoic methyl ester, octadecenoic methyl ester, 9,12-octadecadienoic methyl ester, 10-octadecenoic methyl ester, 2-hexyl cyclopropaneoctanoic methyl ester, eicosanoic methyl ester, 10-heptadecen-8-ynoic acid methyl ester, nonahexacontanoic methyl ester, and tetracosanoic methyl ester.

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Chen, Jin Si, Xian Guo Hu, Xiang Yang Wang, Yu Fu Xu i En Zhu Hu. "Kinetic Investigations of Biodiesel from Cottonseed Oil and Ethanol by Transesterification in Biomaterial and its Application". Advanced Materials Research 578 (październik 2012): 73–77. http://dx.doi.org/10.4028/www.scientific.net/amr.578.73.

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The kinetics of transesterification for biodiesel produced by cottonseed oil and ethanol in catalyst (potassium hydroxide) was investigated. The reaction of transesterification can be described by pseudo second order model for the initial stages of the reaction, followed by zero order reaction. The reaction rate constants for transestentcation of cottonseed oil with ethanol at 40°C, 60°C and 78°C are 0.0996, 0.1126and0.1286 L•mol-1/min-1 respectively, and the activation energy of transesterification is 21.6075kJ/mol．

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Zhu, Fen Fen, Juan Juan Qi, Xiang Wei, Lu Yao Zhao i Yi Qun Xiong. "In Situ Transesterification of Sewage Sludge for Biodiesel Production". Applied Mechanics and Materials 768 (czerwiec 2015): 520–25. http://dx.doi.org/10.4028/www.scientific.net/amm.768.520.

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To develop new clean energy has become an urgent task for many countries forced by the energy and environment crisis. To make biodiesel from sewage sludge is one of the solutions. In this study, biodiesel production from sewage sludge by in situ transesterification was discussed. The solvent is methanol and catalyst is sulfuric acid. In-situ transesterification, has many merits over conventional transesterification reaction such as it simply the procedure by skipping the step of lipid extraction and as a result cost can be saved. That is, the steps — sludge dissolved, lipid extraction and transesterification reactions — take place simultaneously. Methanol acts as an extraction solvent and as an esterification reagent as well. Experiments were conducted to determine the optimal parameters of in-situ transesterification for maximizing the yield of biodiesel, which are methanol to sludge mass ratio, acid concentration and temperature. The optimum synthesis condition was determined by orthogonal test L16 (43), and it was found that an optimum biodiesel yield can be obtained from sewage sludge by in-situ transesterification (16.6%) at methanol to sludge mass ratio 10:1(w/w), H2SO4 concentration 5% (v/v), and temperature 65°C. Temperature, H2SO4 concentration, and methanol to sludge mass ratio in sequence had significant influence on FAMEs yield. The FAMEs in the product were analyzed by GC-MS and the purity can be higher than 96%.

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Salaheldeen, Mohammed, Abdalbasit Adam Mariod, Mohamed Kheireddine Aroua, S. M. Ashrafur Rahman, Manzoore Elahi M. Soudagar i I. M. Rizwanul Fattah. "Current State and Perspectives on Transesterification of Triglycerides for Biodiesel Production". Catalysts 11, nr 9 (18.09.2021): 1121. http://dx.doi.org/10.3390/catal11091121.

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Triglycerides are the main constituents of lipids, which are the fatty acids of glycerol. Natural organic triglycerides (viz. virgin vegetable oils, recycled cooking oils, and animal fats) are the main sources for biodiesel production. Biodiesel (mono alkyl esters) is the most attractive alternative fuel to diesel, with numerous environmental advantages over petroleum-based fuel. The most practicable method for converting triglycerides to biodiesel with viscosities comparable to diesel fuel is transesterification. Previous research has proven that biodiesel–diesel blends can operate the compression ignition engine without the need for significant modifications. However, the commercialization of biodiesel is still limited due to the high cost of production. In this sense, the transesterification route is a crucial factor in determining the total cost of biodiesel production. Homogenous base-catalyzed transesterification, industrially, is the conventional method to produce biodiesel. However, this method suffers from limitations both environmentally and economically. Although there are review articles on transesterification, most of them focus on a specific type of transesterification process and hence do not provide a comprehensive picture. This paper reviews the latest progress in research on all facets of transesterification technology from reports published by highly-rated scientific journals in the last two decades. The review focuses on the suggested modifications to the conventional method and the most promising innovative technologies. The potentiality of each technology to produce biodiesel from low-quality feedstock is also discussed.

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Suzana, Suzana, Nunuk Irawati i Tutuk Budiati. "Synthesis Octyl P-Methoxycinnamate as Sunblock by Transesterification Reaction with the Starting Material Ethyl P- Methoxycinnamate". Indonesian Journal of Cancer Chemoprevention 2, nr 2 (28.06.2011): 217. http://dx.doi.org/10.14499/indonesianjcanchemoprev2iss2pp217-221.

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Synthesis octyl p-methoxycinnamate substance as sunblock, has been done by transesterification reaction. The starting material of the reaction was ethyl p-methoxycinnamate isolated from Kaempferia galanga L.The transesterification reaction was carried out by reacting ethyl p-methoxycinnamate with octanol. The product was identified by UV-VIS,Infra Red and Mass Spectroscopy. The result of measurements on erythemic %T at various concentrations demonstrate that octyl p-methoxycinnamate is applicable as a sunblock compound.Keywords: octyl p-methoxycinnamate, transesterification, ethyl p-methoxycinnamate, sunblock

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Musta, Rustam, Aceng Haetami i Mimi Salmawati. "Biodiesel Hasil Transesterifikasi Minyak Biji Nyamplung (Calophyllum inophyllum) Dengan Metanol". Indo. J. Chem. Res. 4, nr 2 (31.01.2017): 394–401. http://dx.doi.org/10.30598//ijcr.2017.4-rus.

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Study of the transesterification of Calophyllum innophyllum seed oil from Kendari with methanol has been conducted. The purpose of the research to determine of the yield of ester produced in transesterification process with methanol, the viscosity of biodiesel produced, moisture content of biodiesel produced, density of biodiesel produced. The methods used in this study are sample preparation, transesterification process, biodiesel quality parameter test consisting of viscosity, moisture content and density. The results showed that good concentration of phosphoric acid was used to remove the gum is 85%, the yield of ester produced in the process of transesterification with methanol is 111,647%, parameter of biodiesel quality measured that viscosity = 0,315 mm2/ s not fulfill Indonesian National Standart (INS), water content is 0.02 meets the INS and the density = 0.8725 g / cm3 meets the INS standard

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Sereda, Grigoriy, Swetha Pothula i James Dreessen. "Sodium Borohydride–Mediated Transesterification". Synthetic Communications 40, nr 9 (7.04.2010): 1312–21. http://dx.doi.org/10.1080/00397910903072438.

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Bladon, P., M. Warner i M. E. Cates. "Transesterification in nematic polymers". Macromolecules 26, nr 17 (sierpień 1993): 4499–505. http://dx.doi.org/10.1021/ma00069a015.

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Trapasso, Louis E., Philip L. Meisel, Lee B. Meisel i Willy K. Chwang. "5606103 Organotin catalyzed transesterification". Journal of Molecular Catalysis A: Chemical 125, nr 2-3 (listopad 1997): 178. http://dx.doi.org/10.1016/s1381-1169(98)80103-9.

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Zubillaga, M. P., i G. Maerker. "Transesterification of cholesteryl esters". Journal of the American Oil Chemists' Society 65, nr 5 (maj 1988): 780–82. http://dx.doi.org/10.1007/bf02542531.

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Ahmad, Wayez R., i Mark E. Davis. "Transesterification on ?imprinted? silica". Catalysis Letters 40, nr 1-2 (1996): 109–14. http://dx.doi.org/10.1007/bf00807466.

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Platé, Nikolay A., Arkady D. Litmanovich, Yaroslav V. Kudryavtsev i Konstantin V. Demidenok. "Microtacticity changes during transesterification". Journal of Applied Polymer Science 105, nr 1 (2007): 60–66. http://dx.doi.org/10.1002/app.26089.

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Orynbayev, Nursultan, Marat Aldabergenov, Kemal Zhaхylyk i Nurlan Abdildin. "Substantiation of parameters for the inertial mixer in a biodiesel production reactor". Eastern-European Journal of Enterprise Technologies 5, nr 6 (113) (29.10.2021): 39–45. http://dx.doi.org/10.15587/1729-4061.2021.243079.

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This paper reports results of the theoretical and experimental studies into the processes of transesterification of oils with methyl alcohol, which determined the material balance and established the molecular weight of the components involved in the process of transesterification as input and output products. The theoretical and experimental studies were carried out to calculate the indicators of the process of transesterification of fat-containing wastes depending on a change in the reaction duration and diameter of the inertial mixer of the reactor to accelerate the process of transesterification of oils with methyl alcohol. The process of transesterification is one of the basic methods for modifying the molecular composition of fat raw materials. With transesterification, the composition of fat fatty acids does not change, their statistical redistribution occurs in a mixture of triacylglycerols, which leads to a change in the physicochemical properties of fat mixtures as a result of changes in molecular composition. Transesterification of high-melting animal and vegetable fats with methyl alcohol improves the conversion of oils for the production of biodiesel from fat-containing waste. The results of the theoretical and experimental studies have helped determine the value of the flow rate of the reaction mixture, as well as the values of the geometric dimensions of the reactor, were determined (the diameter of the mixer, d=100÷500 mm; the length of the reactor is 1.5÷2.0 m). Processing of the reaction mixture made it possible to obtain a high degree of homogeneity in the concentration of components with large diameters of the inertial mixer ‒ 300...500 mm at average rotational speeds. The oil conversion has been improved, as well as productivity, by using equipment to produce biodiesel from fat-containing waste. Optimal pump performance is also ensured with minimal power consumption and reactor operation

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DE BONI, Luis Alcides Brandini, Tânia Renata PROCHNOW i Gilnei Carvalho OCÁCIA. "PRODUCTION OF SECOND GENERATION CATALYSTS FROM THE RECYCLING OF CATALYSTS USED FOR THE PRODUCTION OF BIODIESEL". Periódico Tchê Química 06, nr 11 (20.01.2009): 43–47. http://dx.doi.org/10.52571/ptq.v6.n11.2009.44_periodico11_pgs_43_47.pdf.

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This article describes the methodology used to recover and reuse the catalyst used in the production of a synthetic liquid fuel obtained by the transesterification reaction of beef tallow with an alcoholic solution of potassium hydroxide. The potassium hydroxide recovered from the transesterification reaction by-product in the form of KH2PO4 was converted into KCl and was subsequently used to produce a catalyst (KOCH3) used in the production of biodiesel. The recycled catalyst was successfully used in a transesterification reaction producing biodiesel and crude glycerol.

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Mohd Alias, Nor Saadah, Harumi Veny, Fazlena Hamzah i Noorhaliza Aziz. "Effect of Free Fatty Acid Pretreatment to Yield, Composition and Activation Energy in Chemical Synthesis of Fatty Acid Methyl Ester". Indonesian Journal of Chemistry 19, nr 3 (29.05.2019): 592. http://dx.doi.org/10.22146/ijc.34492.

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Transesterification of waste cooking oil (WCO) for fatty acid methyl ester synthesis using calcium oxide (CaO) as a catalyst with absence and presence of free fatty acid (FFA) pretreatment (untreated and pretreated) prior to reaction have been investigated. The preliminary study was started from theoretical stoichiometric amount molar ratio of methanol to oil. This preliminary experiment showed that indeed, in transesterification with the chemical catalyst the molar ratio of methanol to oil should be exceeding the theoretical stoichiometric molar ratio, due to the fast reversible reaction. The highest FAME content of 81% was achieved at a temperature of 75 °C with pretreated FFA. The composition of methyl ester with pretreated FFA was affected by temperature, where increasing temperature leads to increasing of methyl oleate as major methyl ester in the product. The relation of temperature dependence was further studied by Arrhenius law correlation. It is shown that activation energy was affected by pretreatment of fatty acid. The activation energy (Ea) of transesterification with untreated and pretreated free fatty acid were found as ± 16 kJ/mol and ± 68 kJ/mol, respectively. Unlike untreated FFA, the Ea of transesterification with pretreated FFA was within the range of activation energy for transesterification for the base catalyst. This study showed that methyl ester synthesis was best obtained when FFA was pretreated prior to transesterification. In addition, WCO is a potential feedstock for biodiesel production since it is biodegradable, economic, environmentally friendly and abundantly available.

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Tahya, Kartika, Candra Yulius Tahya i Healthy Kainama. "Transesterifikasi Minyak Ikan Perak (Mene maculata) Dengan Katalis CaO Dari Cangkang Telur Ayam". Indo. J. Chem. Res. 7, nr 1 (31.07.2019): 69–76. http://dx.doi.org/10.30598//ijcr.2019.7-can.

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Silver fish (Mene maculata) is a type of pelagic fish found in the Moluccas sea, this fish has a high oil content so that it is easy to extract the oil content for transesterification. The transesterification reaction of oil from silver fish oil needs a catalyst, and heterogenous catalyst is a better choice. This study was determined the fatty acid methyl ester composition of M. maculata by transesterification process using heterogeneous CaO catalyst from chicken egg shells through 3 steps i.e. oil isolation, CaO catalyst synthesis, and oil transesterification reactions. Oil isolation was carried out by soxhletation method using petroleum ether with the oil content was 13.51%. Synthesis of CaO catalyst was carried out by calcination at 1000 °C for 2 hours and then charactererized by XRD. Fish oil is transesterified using CaO catalyst in a ratio of 11% (w/v) of the mixture. Furthermore, fatty acid methyl esters obtained were analyzed using GC-MS. The results showed 6 methyl ester fatty acids as composition of transesterification products which were methyl myristic (11.85%), methyl palmitoleate (8.71%), methyl palmitic (25.13%), methyl oleic (9.49%), methyl stearic (10.04%), and methyl 5,8,11,14-eikosatetraenoate (1.96%).

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Tahya, Kartika, Candra Yulius Tahya i Healthy Kainama. "Transesterifikasi Minyak Ikan Perak (Mene maculata) Dengan Katalis CaO Dari Cangkang Telur Ayam". Indo. J. Chem. Res. 7, nr 1 (31.07.2019): 69–76. http://dx.doi.org/10.30598//ijcr.2020.7-can.

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Silver fish (Mene maculata) is a type of pelagic fish found in the Moluccas sea, this fish has a high oil content so that it is easy to extract the oil content for transesterification. The transesterification reaction of oil from silver fish oil needs a catalyst, and heterogenous catalyst is a better choice. This study was determined the fatty acid methyl ester composition of M. maculata by transesterification process using heterogeneous CaO catalyst from chicken egg shells through 3 steps i.e. oil isolation, CaO catalyst synthesis, and oil transesterification reactions. Oil isolation was carried out by soxhletation method using petroleum ether with the oil content was 13.51%. Synthesis of CaO catalyst was carried out by calcination at 1000 °C for 2 hours and then charactererized by XRD. Fish oil is transesterified using CaO catalyst in a ratio of 11% (w/v) of the mixture. Furthermore, fatty acid methyl esters obtained were analyzed using GC-MS. The results showed 6 methyl ester fatty acids as composition of transesterification products which were methyl myristic (11.85%), methyl palmitoleate (8.71%), methyl palmitic (25.13%), methyl oleic (9.49%), methyl stearic (10.04%), and methyl 5,8,11,14-eikosatetraenoate (1.96%).

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Harmiansyah. "Analisis Pengaruh Jumlah Variasi Katalis MeOH Pada Pembuatan Biodiesel Melalui Proses Transesterifikasi". Jurnal Elektro dan Mesin Terapan (ELEMENTER), Vol. 9 No. 1 (2023) (31.05.2023): 113–20. http://dx.doi.org/10.35143/elementer.v9i1.5927.

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Biodiesel is a bioenergy or biofuel produced by transesterification of vegetable oil (animal fat). Transesterification is a chemical method in which oil triglycerides react with methanol with the help of an alkaline catalyst to produce biodiesel. The goal of this study is to determine the quality of biodiesel utilizing MeOH as a catalyst throughout the transesterification process. This study aims to produce biodiesel using the transesterification process with palm oil as the main raw material. Making biodiesel begins with heating the palm oil at 61-65 oC and then adding a mixture of NaOH and methanol solutions so that glycerol, emulsion, and biodiesel are obtained as a result of transesterification. Finally, a separatory funnel is used to obtain pure biodiesel. The yield values of biodiesel produced with MeOH catalysts of 20%, 25%, and 30% were 81.5%, 86.6%, and 44.4%, respectively. Furthermore, this study performed density calculations that influenced the quality of biodiesel from each amount of MeOH utilized to achieve a density of 0.85 g/ml. As can be observed, the usage of MeOH catalyst has an effect on the quality of biodiesel yields.

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Astam, Amal, Laily Nurliana i La Ode Kadidae. "Sintesis Metil Ester Nitrat dari Minyak Biji Nyamplung (Calophyllum inophyllum L)". Hydrogen: Jurnal Kependidikan Kimia 7, nr 2 (10.01.2020): 82. http://dx.doi.org/10.33394/hjkk.v7i2.1927.

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Research on the synthesis of methyl ester nitrate from nyamplung seed oil (Calophyllum inophyllum L.). The aims of study are to are to determine the nitrate methyl ester can be synthesized from nyamplung seed oil determine the yield of the transesterification and nitration reaction from nyamplung seed oil. In this study nyamplung seed oil was obtained from pressing nyamplung seeds using a hydraulic press, then the crude oil obtained was subsequently degumming to remove gum. Free oil of the etherified gum then transesterification with methanol. The transesterification results are then titrated and produce nitric methyl esters. Characterization of nitric methyl ester by spectrophotometer IR shows functional groups C-ONO2, C=C dan C-NO2 at wave number 1635,64 cm-1 1550,77 cm-1 dan 1365, 60 cm-1. The yield of transesterification of nyamplung oil was 64.66% and the nitration yield was 10.6%.

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Bi, Yong Guang, i Shan Shan Wu. "Orthogonal Optimization of Ultrasound-Assisted Ionic Liquid Transesterification of Corn Oil Biodiesel". Advanced Materials Research 791-793 (wrzesień 2013): 196–99. http://dx.doi.org/10.4028/www.scientific.net/amr.791-793.196.

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In order to optimize the ultrasound-assisted corn oil biodiesel transesterification process conditions, factors four through five levels of orthogonal test to optimize their processes, the findings indicate that ultrasound-assisted transesterification of corn oil biodiesel optimum conditions : 1:11 molar ratio of methanol to oil, corn oil catalyst was 11%, the reaction temperature is 90 °C, reaction time was 50min, ultrasonic power 360W, under these conditions, the measured ratio of the average of the transesterification 91.85 %. Relative to conventional preparation methods, the method is simple, rapid, saving solvent consumption and other advantages.

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Tanase, Constantin I., Constantin Draghici, Miron Teodor Caproiu i Ana Cojocaru. "Transeterification of the Intermediate Chloro-ester Compounds in the Sequence for Obtaining Corey Aldehyde Protected as Cyclic Acetals". Revista de Chimie 68, nr 2 (15.03.2017): 260–64. http://dx.doi.org/10.37358/rc.17.2.5432.

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Transesterification of the TBDMS-bis-protected compounds 10-1a and 10-2a with K2CO3 in methanol takes place with the cleavage of the secondary TBDMS group to compounds 13-1 and 13-2. The same compounds were obtained as proof of the transesterification of the bis-benzoate compounds 10-1b and 10-2b. In case of bis-THP protected compounds 10-1c and 10-2c, the secondary THP group, stable in base conditions, was expected not to be removed in transesterification conditions, resulting the compounds rezultind compusii 13-1c and 13-2c.

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Widianto, Tri Nugroho, i Bagus Sediadi Bandol Utomo. "Utilization of fish oil for biodiesel production". Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology 5, nr 1 (1.05.2010): 15. http://dx.doi.org/10.15578/squalen.v5i1.42.

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Recenty fossil fuel consumption gradually increases, resulting in decreases of its naturalresource and causing environmental problems such as air pollution and global warming.Attempts to overcome the problems have been made to create on alternative energy such asbiodiesel from jatropha, microalgae and fish oil. Biodiesel production, as matter of fact, can beconducted using industrial wastes of fish meal, fish fillets and fish canning by transesterification offish oil using methanol and alkaline catalyst. Transesterification reaction kinetics must beconsidered for an efficient process. Transesterification rate constant very much depends on thetemperature and the quantity of the catalyst

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Aljendeel, Haider, Ehab Borhan i Mohammed J. Al-Ani. "Kinetic Study of Transesterification Reaction of Edible Oil Using Heterogenous Catalyst". Iraqi Journal of Chemical and Petroleum Engineering 23, nr 3 (30.09.2022): 11–16. http://dx.doi.org/10.31699/ijcpe.2022.3.2.

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AlPO4 solid acid catalyst was prepared in order to use it in transesterification reaction of edible oil after supporting it with tungsten oxide. The maximum conversion of edible oil was obtained 78.78% at catalyst concentration (5gm.), temperature 70°Ϲ, 30/1 methanol/edible oil molar ratio, and time 5hr. The study of kinetics of the transesterification reaction of edible oil indicates that the reaction has an order of 3/2, while the value of activation energy for transesterification reaction is 51.367 kJ/mole and frequency factor equal 26219.13(L/ mol.minute).

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Donatus Setyawan Purwo Handoko. "Utilization of Waste Tobacco (Nicotiana Tabacum) Post-Harvest as an Alternative Biodiesel". Jurnal Multidisiplin Madani 2, nr 12 (29.12.2022): 4343–49. http://dx.doi.org/10.55927/mudima.v2i12.1780.

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The aims of this research is process into biodiesel. Biodiesel is produced using transesterification reactions with variations of tempetature. Tobacco seed oil is extracted to obtain edible oils as biodiesel. The content of free fatty acid (FFA) in edible oils should be minimized to obtain a high yield of transesterification. The catalyst used in converting edible oils into biodiesel is homogeneous alkaline catalyst. Biodiesel with the higest yield from transesterification reactions with a temperature of 70 oC. Biodiesel was characterized the functional group and phsycal properties including density and viscosity

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Zhou, Zibo, i Guozhang Wu. "Preparation of Bisphenol-A and Polydimethylsiloxane (PDMS) Block Copolycarbonates by Melt Polycondensation: Effects of PDMS Chain Length on Conversion and Miscibility". Polymers 13, nr 16 (10.08.2021): 2660. http://dx.doi.org/10.3390/polym13162660.

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This study aimed to improve polydimethylsiloxane (PDMS) conversion in the preparation of polycarbonate (PC)–polydimethylsiloxane (PDMS) copolymer through melt polycondensation. We examined the transesterification process of PDMS with diphenyl carbonate (DPC) and its copolymerization products with bisphenol-A (BPA) for different chain lengths of PDMS. The key factors affecting PDMS conversion were investigated. Results showed that long-chain PDMS required a higher critical transesterification level (38.6%) to improve miscibility with DPC. During polycondensation, side reactions were more prone to occur when the equilibrium transesterification level of long-chain PDMS was lower. PDMS conversion was also lower when more short-chain PDMS was fed. Increasing the chain length of PDMS also reduced PDMS conversion. Notably, increasing the amount of KOH can significantly improve PDMS conversion throughout the polycondensation stage by increasing the equilibrium transesterification level of long-chain PDMS, thereby inhibiting the occurrence of side reactions.

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Salawu, F. B., A. A. Otori, K. Mohammed i J. T. Mathew. "Optimization of Transesterification Parameters of Biodiesel Produced from Sword Bean (Cavalia gladiate) Seed Oil". Journal of Applied Sciences and Environmental Management 27, nr 1 (31.01.2023): 147–54. http://dx.doi.org/10.4314/jasem.v27i1.21.

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The subject of this study was to optimize the transesterification parameters of biodiesel produced from sword bean (C. gladiate) using Response Surface Methodology (RSM). Four transesterification parameters (Reaction temperature 55 0C, Catalyst concentration 0.4 wt%, Methanol to oil ratio 4:1 and reaction time 60 min) were optimized. Data obtained revealed that the optimum reaction conditions for the transesterification of C. gladiata seed oil resulted in 92.88% biodiesel yield. Multiple regression analysis produced a quadratic polynomial equation for methylester and a linear relationship was recorded between the observed and predicted value (R2 = 0.9647) with a significant molar ratio and temperature. The interaction terms of methanol to oil, molar ratio and temperature with reaction time exhibited a positive effect on the methylester yield. The response surface methodology was found to be a suitable technique for optimizing transesterification process and producing biodiesel that meets the ASTM standard.

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Widjanarko, Dwi, Ratna Dewi Kusumaningtyas i Ahmad Afwan Fathoni. "Alteration of Biodiesel Properties and Automotive Diesel Engine Performance due to Temperature Variation of the Transesterification Process". Jurnal Rekayasa Kimia & Lingkungan 15, nr 2 (17.08.2020): 90–98. http://dx.doi.org/10.23955/rkl.v15i2.16007.

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This study aimed to examine the effects of transesterification reaction temperature on the biodiesel properties and diesel engine performance. Biodiesel properties evaluated in this work included viscosity, density, and methyl ester content. Meanwhile, the diesel engine performance testing comprised the examination of the engine’s torque and power. The research was conducted in several stages, viz. producing biodiesel from fresh cooking oil with variations in transesterification temperature of 45℃, 55℃, and 65℃; testing the characteristics of biodiesel produced; blending biodiesel with petroleum diesel to result in B30 biodiesel fuel; and testing biodiesel fuel (B30) in diesel-engined vehicles. It was revealed that the higher transesterification temperature led to the lower biodiesel viscosity, the decreasing value of biodiesel density values, and the higher methyl ester content. Furthermore, it was also demonstrated that increase of the transesterification temperature resulted in the higher value of torque and power generated. However, compared to the petroleum diesel fuel (B0), biodiesel fuel (B30) exhibited the lower values of the engine’s torque and power. The highest average values of torque and power of B30 fueled diesel-engine were 108.11 Nm and 43.51 kW, respectively, provided by the biodiesel produced at the transesterification reaction temperature of 65℃.of 65℃.

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Yoeswono, Yoeswono, Triyono Triyono i Iqmal Tahir. "KINETICS OF PALM OIL TRANSESTERIFICATION IN METHANOL WITH POTASSIUM HYDROXIDE AS A CATALYST". Indonesian Journal of Chemistry 8, nr 2 (17.06.2010): 219–25. http://dx.doi.org/10.22146/ijc.21625.

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A study on palm oil transesterification to evaluate the effect of some parameters in the reaction on the reaction kinetics has been carried out. Transesterification was started by preparing potassium methoxide from potassium hydroxide and methanol and then mixed it with the palm oil. An aliquot was taken at certain time interval during transesterification and poured into test tube filled with distilled water to stop the reaction immediately. The oil phase that separated from the glycerol phase by centrifugation was analyzed by 1H-NMR spectrometer to determine the percentage of methyl ester conversion. Temperature and catalyst concentration were varied in order to determine the reaction rate constants, activation energies, pre-exponential factors, and effective collisions. The results showed that palm oil transesterification in methanol with 0.5 and 1 % w/w KOH/palm oil catalyst concentration appeared to follow pseudo-first order reaction. The rate constants increase with temperature. After 13 min of reaction, More methyl esters were formed using KOH 1 % than using 0.5 % w/w KOH/palm oil catalyst concentration. The activation energy (Ea) and pre-exponential factor (A) for reaction using 1 % w/w KOH was lower than those using 0.5 % w/w KOH. Keywords: palm oil, transesterification, catalyst, first order kinetics, activation energy, pre-exponential factor

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