scholarly journals The Unanticipated Catalytic Activity of Lithium tert-Butoxide/THF in the Interesterification of Rapeseed Oil with Methyl Acetate

2019 ◽  
Vol 2019 ◽  
pp. 1-6 ◽  
Author(s):  
Valdis Kampars ◽  
Zane Abelniece ◽  
Sabine Blaua
Keyword(s):  
Catalytic Activity ◽  
Rapeseed Oil ◽  
Methyl Acetate ◽  
Methyl Esters ◽  
Ion Pairs ◽  
Molar Ratio ◽  
Fast Reaction ◽  
Branched Chain ◽  
Association Of Ions ◽  
Sodium And Potassium

Conventionally, the biodiesel (mixture of fatty acid methyl esters, FAME) production proceeds by transesterification of triglycerides with methanol accordingly by the formation of glycerol as a by-product, which cannot be included in biofuel composition. Biodiesel could also be produced via interesterification ensuring full conversion of oil to biofuel, consisting of FAME and triacetin. The most effective catalysts for interesterification reactions are alkali metal alkoxides. The effectivity of alkoxide catalyst depends on its solubility determined by the structure of the alkyl chain. In our previous studies, we have shown that the branched chain catalyst tert-BuOK/THF is highly suitable for the realisation of interesterification reactions. Till now, in the scientific literature, very little is known about the influence of metal ions. In order to investigate the influence of counterion on the activity of alkoxide catalysts, in this work, we have investigated the proceeding of interesterification reactions of rapeseed oil with methyl acetate in the presence of lithium, sodium, and potassium tert-butoxides in THF. Experimentally obtained relationships for catalyst-to-oil molar ratio (COMR) influence rapeseed oil interesterifications with methyl acetate at 55°C for 1 h, with methyl acetate-to-oil molar ratio (MAOMR) 18 showing that the tert-BuONa/THF and tert-BuOK/THF have high and similar activity, but the tert-BuOLi/THF is fundamentally different. The low and diverse activity of lithium tert-butoxide can be explained by the association of ions and very low catalytic activity of ion pairs. Simulation of the influence of association on the FAME formation shows that at COMR 0.1 (sufficient for fast reaction proceeding in the presence of tert-BuONa/THF and tert-BuOK/THF), the concentration of tert-butoxide ions in the presence of tert-BuOLi/THF because of associations lowers from 28 mmol/L to 13 mmol/L, whcih is not sufficient for effective proceeding of reaction. Activity of alkoxides in this reaction is solely determined by the counterion.

A Novel Route for Conversion of Free Fatty Acids in Acidic Oils to Methyl Esters by In-Situ Hydrolysis of Methyl Acetate

2011 ◽  
Vol 9 (1) ◽  
Author(s):  
Vijaya Lakshmi Ch ◽  
Uday Bhaskar R.V.S ◽  
Viswanath Kotra ◽  
Satyavathi Bankupalli
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Methyl Acetate ◽  
Edible Oils ◽  
Methyl Esters ◽  
Maximum Yield ◽  
Molar Ratio ◽  
Esterification Reaction ◽  
Higher Alcohol

Biodiesel from clean oils is comparatively easier than production from crude and non-edible oils. To achieve maximum yield of biodiesel, a two stage process is adopted in which non-edible oils are used as feed-stock: an acid catalyzed esterification of free fatty acids followed by base catalyzed transesterification. Presence of water formed during esterification reaction is detrimental to a viable transesterification process. In the present work, an alternate method for removal of water by in situ hydrolysis reaction of methyl acetate is introduced. The dehydration using methyl acetate during esterification has yielded good results as the soap formed during transesterification was minimal. The results indicated high conversion of triglycerides to methyl ester for lower oil to methanol ratio and at a lower temperature. For 1:3 molar ratio of oil to methanol, the conversion obtained was less than 90 percent and is equivalent to conversions with higher alcohol ratios during esterification in the absence of methyl acetate. These results are indicative of the fact that use of methyl acetate reduces the alcohol to oil ratio without affecting the conversions. Moreover, higher conversions are possible at lower temperatures in the presence of methyl acetate. It is further observed that the oils that are subjected to free fatty acid conversions in the presence of methyl acetate record very little soap formation during the transesterification reactions, thereby resulting in higher grade of biodiesel.

scholarly journals Biocatalytic transesterification of rapeseed oil by methyl formate

2019 ◽  
Vol 26 (1) ◽  
Author(s):  
Violeta Makarevičienė ◽  
Ieva Sendžikaitė
Keyword(s):  
Fatty Acid ◽  
Rapeseed Oil ◽  
Methyl Formate ◽  
Methyl Esters ◽  
Fatty Acid Esters ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Raw Glycerol ◽  
Alternate Source ◽  
Biochemical Research

Due to the awareness of adverse effects of conventional fuels on environment and on a frequent rise in the crude oil price, the need for a sustainable and environment-friendly alternate source of energy has gained importance. Recently, options have been analysed to replace the triglyceride transesterification process, which is generally used in biodiesel production, by the process where raw glycerol is not generated, whereas triacylglycerides obtained instead glycerol can be directly used as fuel for a diesel engine in a mixture with fatty acid esters. In the present work, interesterification of rapeseed oil to biodiesel was carried out with methyl formate and using lipase as a catalyst. The research was carried out at the Laboratory of Chemical and Biochemical Research for Environmental Technology of Aleksandras Stulginskis University. First, the most effective biocatalyst suitable for the process was selected. 14 different lipases were studied. The samples obtained after the synthesis were analysed by the thin-layer and gas chromatography. Process experiments were performed using a methyl formate to oil molar ratio of 6:1 to 40:1, a lipase amount of 5 to 17% (mass of oil) and synthesis duration of 3 to 48 h. The highest yield of fatty acid methyl esters (FAME) was obtained using Lipozyme RM IM as a catalyst and its optimal amount was 13%. The optimal temperature was found to be 20°C and the duration of interesterification 42 h. The optimal molar ratio of methyl formate to oil was determined to be 32:1. Under the obtained conditions the transesterification degree was 60.68 ± 0.95%.

scholarly journals Biodiesel Production by Esterification Reaction on K+ Modified MgAl-Hydrotalcites Catalysts

Catalysts ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 742 ◽  
Author(s):  
Chen-Yang Zhang ◽  
Wen-Li Shao ◽  
Wei-Xia Zhou ◽  
Yang Liu ◽  
Yuan-Yuan Han ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Rapeseed Oil ◽  
Load Ratio ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Esterification Reaction ◽  
Solid Base ◽  
High Catalytic Activity ◽  
Temperature Programmed ◽  
Co Precipitation

K+ modified hydrotalcites and its activity as a solid base catalyst for ultrasonic wave- assisted biodiesel conversion was investigated. The solid alkaline catalysts of the MgAl-hydrotalcites (HT) was prepared by co-precipitation and modified with K+ by impregnation. The influence of K+ incorporation on the performance of Mg-Al hydrotalcites catalysts was investigated by SmartLab X-ray powder diffractometer (XRD), infrared spectrum (IR), thermogravimetric-differential thermal analysis (TG–DTA), CO2 temperature programmed desorption (CO2-TPD), scanning electron microscopy (SEM), and N2 adsorption–desorption isotherm (BET). The research discovered that K+ modified of double layered structure of MgAl-hydrotalcite resulted in a significant increase in catalytic activity in transesterification of rapeseed oil. It exhibited high catalytic activity that achieved a biodiesel yield of 99% when the reaction was conducted with 2 wt% catalysts, K+/HT load ratio of 6.25%, a methanol/rapeseed oil molar ratio of 12:1, and reaction at 60 °C over 1 h. The result showed that the K+ modified HT as a transesterification catalyst had the potency for biodiesel conversion. In addition, under the above reaction conditions, the biodiesel yield was up to 99.9% in only five minutes with ultrasonic aid.

Rapeseed Oil Interesterification Reaction with Metylacetate in the Presence of BuOK/BuOH at Different Temperatures

2019 ◽  
Vol 800 ◽  
pp. 83-87
Author(s):  
Valdis Kampars ◽  
Reinis Gravins ◽  
Kristine Lazdovica
Keyword(s):  
Reaction Time ◽  
Characteristic Time ◽  
Rapeseed Oil ◽  
Methyl Acetate ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
First Order ◽  
Different Temperatures ◽  
Pseudo First Order ◽  
Synthesis Stage

By the investigation and comparison of different interesterification reactions at fixed reaction time researchers usually selected 1 hour as a characteristic time for the synthesis stage of industrial biodiesel production. Investigation performed in this work shows that the equilibrium of interesterification reaction mixture of rapeseed oil with methyl acetate in molar ration of 1:18 in presence of potassium tert-butoxide in tert-butanol at molar ratio to oil 0.08 at 25 °C reach the equilibrium approximately after 50 min but at 55 °C after 10 min. The equilibrium compositions of the reaction mixtures at different temperatures are different. The concentrations of TG, FAME and TA during the interesterification reaction at 25 °C obey the pseudo-first order law which do not reflect the stoichiometry of this multiple elementary steps reaction.

scholarly journals Effect of Temperature on Interesterification of Rapeseed Oil with Methyl Acetate in Presence of BuOK/BuOH

2019 ◽  
Vol 103 ◽  
pp. 02006
Author(s):  
Valdis Kampars ◽  
Reinis Gravins ◽  
Kristine Lazdovica ◽  
Ruta Kampare
Keyword(s):  
Reaction Time ◽  
Rapeseed Oil ◽  
Methyl Acetate ◽  
Order Rate Constant ◽  
Effect Of Temperature ◽  
Molar Ratio ◽  
Optimal Range ◽  
First Order ◽  
Pseudo First Order ◽  
Full Conversion

If the interesterification reaction of rapeseed oil with methyl acetate at reactant to oil molar ratio of 18:1 in presence of potassium tert-butoxide in tert-butanol of molar ratio to oil 0.08 is conducted at a temperature of about 35 °C, reaction time for full conversion of oil is shorter than one hour, while at a temperature of 55 °C it is approximately 15 minutes. Reaction time at the desired temperature has a wide "optimal" range and cannot be an effective variable for the process optimisation. Experimental results at the temperature of 25 °C confirm the pseudo-first order of the reaction, which lowered towards the end of the reaction. The pseudo-first order rate constant was 0.63 min-1. Fuel characteristics of the interesterification reaction mixtures without purification improved with the rising of reaction temperature from 35 °C to 55 °C, however, they fail to meet the requirements of standard EN14214 for biodiesel. Methyl acetate to oil molar ratio 18:1 is too low for obtaining products with kinematic viscosity below 5.0 mm2/s.

scholarly journals Natural Rocks–Heterogeneous Catalysts for Oil Transesterification in Biodiesel Synthesis

Catalysts ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 384
Author(s):  
Ieva Gaide ◽  
Violeta Makareviciene ◽  
Egle Sendzikiene ◽  
Kiril Kazancev
Keyword(s):  
Response Surface Methodology ◽  
Reaction Time ◽  
Heterogeneous Catalysis ◽  
Rapeseed Oil ◽  
Heterogeneous Catalysts ◽  
Methyl Esters ◽  
Molar Ratio ◽  
Optimal Conditions ◽  
Biodiesel Synthesis ◽  
Calcium And Magnesium

Some of the more recent methods to produce biodiesel are based on heterogeneous catalysis, which has the advantage of easy separation of catalyst from the final product. In this paper, the heterogeneous transesterification of rapeseed oil with methanol is studied. The aim of this work was to investigate the possibilities of using natural catalysts in biodiesel synthesis and to determine the optimal conditions for this process. After the evaluation of catalytic effectiveness of rocks containing calcium and magnesium carbonates, it was determined that dolomite is the most effective catalyst in heterogeneous biodiesel synthesis. The optimal conditions of dolomite preparation are the following: heating at 850 °C for 5 h. The rapeseed oil transesterification was optimized by the application response surface methodology. Optimal conditions for the production of rapeseed methyl esters using dolomite as catalyst are the following: molar ratio of methanol to rapeseed oil of 11.94:1, reaction temperature of 64 °C, dolomite content of 6 wt%, reaction time of 5 h.

Mango (Magnifera indica) seed oil grown in Dilla town as potential raw material for biodiesel production using NaOH- a homogeneous catalyst

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Diesel Engine ◽  
Physicochemical Properties ◽  
Seed Oil ◽  
Methyl Esters ◽  
Pollution Prevention ◽  
Raw Material ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Homogeneous Catalyst ◽  
Minimal Amount

Biodiesel produced by transesterification process from vegetable oils or animal fats is viewed as a promising renewable energy source. Now a day’s diminishing of petroleum reserves in the ground and increasing environmental pollution prevention and regulations have made searching for renewable oxygenated energy sources from biomasses. Biodiesel is non-toxic, renewable, biodegradable, environmentally benign, energy efficient and diesel substituent fuel used in diesel engine which contributes minimal amount of global warming gases such as CO, CO2, SO2, NOX, unburned hydrocarbons, and particulate matters. The chemical composition of the biodiesel was examined by help of GC-MS and five fatty acid methyl esters such as methyl palmitate, methyl stearate, methyl oleate, methyl linoleate and methyl linoleneate were identified. The variables that affect the amount of biodiesel such as methanol/oil molar ratio, mass weight of catalyst and temperature were studied. In addition to this the physicochemical properties of the biodiesel such as (density, kinematic viscosity, iodine value high heating value, flash point, acidic value, saponification value, carbon residue, peroxide value and ester content) were determined and its corresponding values were 87 Kg/m3, 5.63 Mm2/s, 39.56 g I/100g oil, 42.22 MJ/Kg, 132oC, 0.12 mgKOH/g, 209.72 mgKOH/g, 0.04%wt, 12.63 meq/kg, and 92.67 wt% respectively. The results of the present study showed that all physicochemical properties lie within the ASTM and EN biodiesel standards. Therefore, mango seed oil methyl ester could be used as an alternative to diesel engine.

Evaluation of Ethoxylated Rapeseed Oil Fatty Acids Methyl Esters as Nonionic Co-Surfactants in Hand Dishwashing Liquids

2019 ◽  
Vol 56 (4) ◽  
pp. 279-286 ◽  
Author(s):  
Tomasz Wasilewski ◽  
Yong-Qiang Sun ◽  
Wiesław Hreczuch ◽  
Artur Seweryn ◽  
Tomasz Bujak
Keyword(s):  
Fatty Acids ◽  
Rapeseed Oil ◽  
Methyl Esters

Efficient Micromixing for Continuous Biodiesel Production from Jatropha Oil

2018 ◽  
Vol 9 (1) ◽  
pp. 133-139
Author(s):  
Waleed S. Mohammed ◽  
Ahmed H. El-Shazly ◽  
Marwa F. Elkady ◽  
Masahiro Ohshima
Keyword(s):  
Methyl Esters ◽  
Continuous Process ◽  
Sol Gel ◽  
Average Diameter ◽  
Biodiesel Production ◽  
High Mass ◽  
Molar Ratio ◽  
Jatropha Oil ◽  
Energy Deficiency ◽  
Gel Preparation

Introduction: The utilization of biodiesel as an alternative fuel is turning out to be progressively famous these days because of worldwide energy deficiency. The enthusiasm for utilizing Jatropha as a non-edible oil feedstock is quickly developing. The performance of the base catalyzed methanolysis reaction could be improved by a continuous process through a microreactor in view of the high mass transfer coefficient of this technique. Materials & Methods: Nanozirconium tungstovanadate, which was synthetized using sol-gel preparation method, was utilized in a complementary step for biodiesel production process. The prepared material has an average diameter of 0.066 &µm. Results: First, the NaOH catalyzed methanolysis of Jatropha oil was investigated in a continuous microreactor, and the efficient mixing over different mixers and its impact on the biodiesel yield were studied under varied conditions. Second, the effect of adding the nanocatalyst as a second stage was investigated. Conclusion: The maximum percentage of produced methyl esters from Jatropha oil was 98.1% using a methanol/Jatropha oil molar ratio of 11 within 94 s using 1% NaOH at 60 &°C. The same maximum conversion ratio was recorded with the nanocatalyst via only 0.3% NaOH.

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