Transesterification of Soybean Oil Catalyzed by Calcium Hydroxide which Obtained from Hydrolysis Reaction of Calcium Carbide

Calcium carbide residue (CCR) was investigated in transesterification reaction of triglycerides to determine its viability as a solid catalyst for biodiesel synthesis. Literature survey showed that CCR has never been studied as a solid catalyst in the transesterification of triglyceride. The scope of the study includes the effects of CCR calcination temperature, calcination time, the alcohol/oil molar ratio, the catalyst amount (wt % of oil) and the reaction time. The relationship between chemical composition and catalytic activity of waste cement was also investigated. These CCR catalysts, thermally activated at 600 °C, can give rise to fatty acid methyl esters (FAME) purity higher than 99.5%, after 3 h of reaction, when oil/methanol molar ratio of 1/12 and 1 wt % of the catalyst were employed. Application of CCR as catalyst for biodiesel production in this study may not only provide a cost‐effective and environment friendly way of recycling CCR waste but also reduce hopefully the cost of biodiesel production.     

基于氯化镁饱和溶液中固定化脂肪酶Lipozyme TL IM催化光皮树油脂合成生物柴油

基于氯化镁饱和溶液反应体系中,对采用固定化脂肪酶Lipozyme TL IM催化光皮树油脂转化为生物柴油的工艺进行了研究。考察了固定化脂肪酶Lipozyme TL IM催化光皮树油转酯化的工艺中甲醇的用量、固定化脂肪酶的添加量、摇床的转速和反应时间对生物柴油产率的影响。实验结果表明,采用氯化镁饱和溶液反应体系,在醇油摩尔比为3∶1,固定化酶Lipozyme TL IM用量为光皮树油质量的20%,摇床转速为150 r/min,反应8 h时,生物柴油产率最高,达到86.5%。与传统的三步甲醇醇解或者有机溶剂反应体系比较,采用的氯化镁饱和溶液体系的酶稳定性更好,反应效率更高,有效地解决了酶在甲醇中失活的问题,生产成本低,可成为生产生物柴油的新工艺。     

Production of biodiesel fuel by transesterification of rapeseed oil

Fatty acid methyl esters (FAMEs) show large potential applications as diesel substitutes, also known as biodiesel fuel. Biodiesel fuel as renewable energy is an alternative that can reduce energy dependence on petroleum as well as air pollution. Several processes for the production of biodiesel fuel have been developed. Transesterification processes under alkali catalysis with short-chain alcohols give high yields of methyl esters in short reaction times. We investigated transesterification of rapeseed oil to produce the FAMEs. Experimental reaction conditions were molar ratio of oil to alcohol, concentration of catalyst, type of catalyst, reaction time, and temperature. The conversion ratio of rapeseed oil was enhanced by the alcohol:oil mixing ratio and the reaction temperature.     

Optimization of Biodiesel Production from Castor Oil Using Response Surface Methodology

The short supply of edible vegetable oils is the limiting factor in the progression of biodiesel technology; thus, in this study, we applied response surface methodology in order to optimize the reaction factors for biodiesel synthesis from inedible castor oil. Specifically, we evaluated the effects of multiple parameters and their reciprocal interactions using a five-level three-factor design. In a total of 20 individual experiments, we optimized the reaction temperature, oil-to-methanol molar ratio, and quantity of catalyst. Our model equation predicted that the following conditions would generate the maximum quantity of castor biodiesel (92 wt.%): a 40-min reaction at 35.5 °C, with an oil-to-methanol molar ratio of 1:8.24, and a catalyst concentration of 1.45% of KOH by weight of castor oil. Subsequent empirical analyses of the biodiesel generated under the predicted conditions showed that the model equation accurately predicted castor biodiesel yields within the tested ranges. The biodiesel produced from castor oil satisfied the relevant quality standards without regard to viscosity and cold filter plugging point.     

Biodiesel Production from Alkali-Catalyzed Transesterification of Tamarindus indica Seed Oil and Optimization of Process Conditions

Biodiesel is considered a sustainable alternative to petro-diesel owing to several favorable characteristics. However, higher production costs, primarily due to the use of costly edible oils as raw materials, are a chief impediment to its pecuniary feasibility. Exploring non-edible oils as raw material for biodiesel is an attractive strategy that would address the economic constraints associated with biodiesel production. This research aims to optimize the reaction conditions for the production of biodiesel through an alkali-catalyzed transesterification of Tamarindus indica seed oil. The Taguchi method was applied to optimize performance parameters such as alcohol-to-oil molar ratio, catalyst amount, and reaction time. The fatty acid content of both oil and biodiesel was determined using gas chromatography. The optimized conditions of alcohol-to-oil molar ratio (6:1), catalyst (1.5% w/w), and reaction time 1 h afforded biodiesel with 93.5% yield. The most considerable contribution came from the molar ratio of alcohol to oil (75.9%) followed by the amount of catalyst (20.7%). In another case, alcohol to oil molar ratio (9:1), catalyst (1.5% w/w) and reaction time 1.5 h afforded biodiesel 82.5% yield. The fuel properties of Tamarindus indica methyl esters produced under ideal conditions were within ASTM D6751 biodiesel specified limits. Findings of the study indicate that Tamarindus indica may be chosen as a prospective and viable option for large-scale production of biodiesel, making it a substitute for petro-diesel.     

Various methods for enhancement in heterogeneous catalysed biodiesel production reaction rate

The biodiesel can be produced by transesterification and esterification reaction with edible and non-edible oil respectively. These reactions are catalysed by both homogeneous and heterogenous catalyst. The transesterification reactions for heterogeneous catalysts proceed at a relatively slow rate. The heterogeneous reaction mixture constitutes a three-phase system, oil/alcohol/catalyst therefore the mass transfer limitation controls the reaction rate. In the present study Tetra-hydrofuran, Hexane and Heptane as co-solvent have been tested for the transesterification and esterification reaction. Tetra-hydrofuran, assists in decreasing the mass transfer between the oil and methanol phases. Tetra-hydrofuran was found to be the best co-solvent. It also represents that the presence of Tetra-hydrofuran only enhance the solubility of phases not final equilibrium yield. Results are compared with homogeneous and heterogeneous catalysed reaction. Ultrasonic irradiation influenced the mixing of the reaction mixture and resulted in higher yields, for each co-solvent case.     

CaO-MgO@CoFe_2O_4磁性固体碱的制备及其大豆油酯交换反应催化性能

以草酸盐为前驱体采用两步法制备了一种以CaO-MgO作为活性组分,以CoFe_2O_4作为磁核的磁性固体碱催化剂,并用于大豆油与甲醇的酯交换反应合成生物柴油。对制备的磁性固体碱催化剂进行了磁滞回线、X-射线衍射(XRD)、CO_2-TPD及透射电镜(TEM)表征。考察了不同核壳物质的量比、焙烧温度、反应温度、反应时间、醇油物质的量比以及催化剂用量等因素对大豆油转化为生物柴油产率的影响。结果表明,采用核壳物质的量比为1∶6、焙烧温度为700℃所制备的CaO-MgO@CoFe_2O_4催化剂,当醇油物质的量比为12、催化剂用量为大豆油质量的1.0%时,在65℃下反应时间3 h,生物柴油收率高达97.1%。该催化剂具有较好的重复利用性能,重复利用四次后生物柴油的收率仍可达90%。     

Application of Flying Jet Plasma for Production of Biodiesel Fuel from Wasted Vegetable Oil

Biodiesel, a good partial or total substitute for petrodiesel, is a renewable clean burning fuel which can be produced from transesterification of vegetable oils and animal fats with an alcohol in presence of a catalyst. Since the feedstock costs in this process constitutes more than 70 % of the overall cost, use of wasted vegetable oil (i.e. consumed cooking oil) for biodiesel production is a big challenge in terms of cost reduction and environmental impacts. Nonetheless, the content of residues in the wasted vegetable oil, formed during frying, is a major drawback could be faced in this direction. In this research, we applied an unconventional design of flying jet dielectric barrier discharge plasma torch to treat several specimens of wasted cooking oil collected from different resources before transesterification. In other experiments, the jet plasma itself was used to catalyze the reaction process. The examined plasma torch was found more feasible than conventional DBD reactor design in terms of gas and power consumptions. Upon inducting plasma treatment, the transesterification process resulted in higher biodiesel yield, lower reaction time and easier product separation than the conventional path. Upon catalyzing the reaction by the sole jet plasma effect, the biodiesel content of saturated methyl esters was higher than conventional tranesterification. Also, the yield and properties were found within commercial standards.     

The use of impregnated perlite as a heterogeneous catalyst for biodiesel production from marula oil

In this study, biodiesel was produced from marula (Sclerocarya birrea) oil using impregnated perlite with potassium hydroxide (KOH) as a heterogeneous catalyst. The effect of experimental variables such as temperature (°C), reaction time (h), methanol to oil ratio (mass %), and catalyst to oil ratio (mass %) on the transesterification process were investigated. Using a central composite design (CCD), a mathematical model was developed to correlate the experimental variables with the percentage yield of biodiesel. The model showed that optimum conditions for biodiesel production were as follows: catalyst to oil ratio of 4.7 mass %, temperature of 70.4°C, methanol to oil ratio of 29.9 mass %, and reaction time of 3.6 h. The yield of 91.4 mass % of biodiesel was obtained. It was also possible to recycle and reuse the modified perlite up to three times without any significant change in its catalytic activity. The X-ray diffraction (XRD) and the Brunauer-Emmett-Teller (BET) surface area showed no modifications in the perlite structure. The results show that the important fuel properties of marula biodiesel meet the American Society for Testing and Materials (ASTM) biodiesel standard properties.     

Thermal and kinetic evaluation of cotton oil biodiesel

The biodiesel obtained by transesterification by reaction between ester and an alcohol in the presence of catalyst. The purpose of this work is to evaluate the thermal and kinetic behavior of the methanol biodiesel derived from cotton oil. The quality analysis was done by gas chromatography and proton nuclear magnetic resonance spectrometry (¹H NMR) in order to examine if the product meets with the requirements of the European Standard EN 1403. The thermogravimetric profile of the cotton biodiesel indicated that the decomposition steps are associated to the volatilization and/or decomposition of the methyl esters. Kinetic data was also obtained by thermal analysis.     

双核碱性离子液体催化棉籽油酯交换制备生物柴油

采用两步法制备了五种新型咪唑类碱性双核功能化离子液体化合物,并考察了对棉籽油酯交换制备生物柴油的催化性能。结果表明,咪唑类碱性双核功能化离子液体具有很好的催化活性,其催化活性与阳离子中碳链长度有关。其中,双-(3-甲基-1-咪唑)亚乙基双氢氧化物离子液体的催化活性最好。催化剂量、反应时间、反应温度及醇油比对生物柴油中脂肪酸甲酯含量及选择性影响的研究发现,在催化剂用量为0.4%(质量分数),醇油摩尔比为12,反应温度为55℃,反应时间为4 h时,脂肪酸甲酯的含量和选择性分别达98.5%和99.9%。催化剂7次循环后,产物中脂肪酸甲酯含量仍达到96.2%,单甘酯和双甘酯的含量很少,表明该催化剂重复使用良好。     

Characterization by TG/DTG/DSC and FTIR of frying and fish oil residues to obtain biodiesel

Biodiesel is a fuel derived from vegetable oils or wastes. It has a lot of advantages such as less offensive exhaust, more complete combustion, reducing emissions of carbon dioxide and sulfur in addition to generating employment and wealth. This biofuel can be produced through the transesterification reaction of an alcohol with a triglyceride, with the aid of a catalyst, resulting on a biodiesel as main product, glycerol, and other byproducts. The objective of this study is to determine the optimal reaction conditions for transesterification of waste frying oil and fish, varying the reaction time, the amount of catalyst and temperature, to determine which of these variables exert a greater influence on the reaction yield, and characterize biofuels obtained. For a more accurate assessment of the influence of a given variable on the reaction yield, it was performed a statistical experimental design, the full factorial of two levels with three parameters (2³) and three central points, implemented in Statistica 7.0. Regarding the transesterification of waste of the fish oil, the amount of catalyst was the variable that most influenced the reaction yield, the parameters time and temperature had negligible impact on income. Biofuels were also characterized using thermal analysis techniques and FTIR. Most reactions obtained thermogravimetric yield above 90%, a promising result.     

Evaluation of the effect of Si/Mo and oil/alcohol ratios in the production of biodiesel from soybean oil

Mo-KIT-6 catalysts precursors obtained by direct hydrothermal synthesis using different Si/Mo molar ratios (10, 20, 30) were evaluated in the production of biodiesel from the transesterification of soybean oil with methanol. A 2² + 3PtCt factorial design was used to evaluate the influence of alcohol/oil and Si/Mo ratios on biodiesel yield. ANOVA statistical analysis showed that Si/Mo ratio was the most significant variable. The factorial design showed that the optimal conditions for maximizing the biodiesel yield are: using the 10_Mo-KIT-6 catalyst, and an alcohol/oil ratio of 20/1 at 150 °C for 3 h. However, using the 20_Mo-KIT-6 catalyst with an alcohol/oil ratio of 15/1 the biodiesel yield is close to the maximum, having the advantage of using a lower amount of methanol, which means that the separation of non-reacted alcohol will consume less energy.     

Castor oil modified by epoxidation,transesterification, and acrylation processes: Spectroscopic characteristics

In the present study, castor oil (CO) was modified by epoxidation, transesterification, and acrylation processes. In situ epoxidation method was used to prepare epoxidized castor oil (ECO) in acetic acid with hydrogen peroxide in the presence of Seralite SRC-120 catalyst. Transesterified epoxidized castor oil was synthesized from the reaction of methanol in the presence of sodium methoxide catalyst. The acrylated epoxidized castor oil was synthesized from the reaction of ECO with acrylic acid containing hydroquinone. Chemical structures of modified CO were analyzed by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectra analysis.     

Thermal stability evaluation of methylic biodiesel obtained for different oilseeds

Biodiesel is defined as a mixture of mono- or di-alquil esters of vegetable oil or animal fats. During long-term storage, oxidation caused by contact with air (autoxidation) presents a legitimate concern in relation to monitoring and maintaining fuel quality. Extensive oxidative degradation may compromise the quality by adversely affecting kinematic viscosity, acid value, or peroxide value. The oxidation susceptibility of biodiesel, due to the presence of triacilglycerides of poly-unsaturated fatty acids, was evaluated in this study. Samples of sunflower, castor, and soybean biodiesels were obtained through the transesterification reaction, with the intention of achieving the thermal stability study through thermogravimetrical analyses and differential scanning calorimetry high pressure. It was furthermore observed through thermogravimetry and pressure differential scanning calorimetry curves that castor biodiesel exhibited the highest thermal and oxidative stability.     

Biodiesel Production via the Transesterification of Soybean Oil Using Waste Starfish (Asterina pectinifera)

Calcined waste starfish was used as a base catalyst for the production of biodiesel from soybean oil for the first time. A batch reactor was used for the transesterification reaction. The thermal characteristics and crystal structures of the waste starfish were investigated by thermo-gravimetric analysis and X-ray diffraction. The biodiesel yield was determined by measuring the content of fatty acid methyl esters (FAME). The calcination temperature appeared to be a very important parameter affecting the catalytic activity. The starfish-derived catalyst calcined at 750 °C or higher exhibited high activity for the transesterification reaction. The FAME content increased with increasing catalyst dose and methanol-over-oil ratio.     

原位共沉淀法制备NiMg(Al)O/γ-Al2O3催化剂及其酯交换性能

以γ-Al₂O₃为载体通过原位共沉淀法制备NiMgAl-LDHs/γ-Al₂O₃,经焙烧后得到NiMg（Al）O/γ-Al₂O₃催化剂,通过TG-DTG、XRD、SEM、BET、FT-IR、CO₂-TPD等手段对催化剂进行了表征,并对其在酯交换制备生物柴油反应中的催化性能进行了研究。结果表明,NiMgAl-LDHs和NiMg（Al）O成功在γ-Al₂O₃内孔表面生长,并有良好的结合度。催化剂对酯交换具有很高的催化活性;在醇油物质的量比为12：1的条件下反应3 h,生物柴油产率为95%,重复使用七次后,生物柴油产率仍然在82%以上。     

The Obtaining Biodiesel from Used Vegetable Oil and Animal Waste Oil by Two Stages Transesterification Reaction

The biodiesel was obtained from used vegetable oil (UVO) and animal waste oil (AWO) by the two stages transesterification reaction. Also chemical and technical properties of feed and products were determined. Conditions of transesterification reaction for each of the oil samples were determined as a result of several sets of experiments. The suitable conditions of transesterification reaction were the following. Hereto a molar ratio of oil: methanol: catalyst was 1: 6: 1/40, for 30 min, at temperature of 600°C. To obtain biodiesel directly by the one stage transesterification, in case of using UVO sample, when the acidity number of feed oil had to less than 3 mg KOH/g. The biodiesel from UVO and AWO was prepared by mixing 5, 10, 20% of volume in the summer and winter diesel fuel. However, the product from mixture of UVO and winter diesel fuel met the technique requirements both of winter and summer diesel fuel, but the product from mixture of AWO and summer diesel fuel did not satisfy technical requirements of diesel fuel.     

Critical review on analytical methods for biodiesel characterization

Biodiesel is an alternative fuel composed of mono-alkyl esters and obtained mainly from the base-catalyzed transesterification reaction of oils or fats. Its use (pure or blended) does not demand any modification in the diesel engine and in the existing fuel distribution and storage infrastructure. Moreover, biodiesel has a high energetic yield, fixes the solar energy and contains insignificant amounts of sulphur. Therefore, biodiesel is currently the best substitute for fossil diesel fuel.Besides mono-alkyl esters, glycerol (main co-product), alcohol, catalyst, free fatty acids, tri-, di- and monoglycerides compose the final mixture of biodiesel production process. These and other kinds of contaminants can lead to severe operational and environmental problems. Therefore, the quality control of biodiesel is greatly significant to the success of its commercialization and market acceptance. Some important issues on the biodiesel quality control involve the monitoring of transesterification reaction, the quantification of mono-alkyl esters and free- and bonded glycerol as well as determination of residual catalysts and alcohol. Moreover, the determination of blend levels is another key aspect of biodiesel analyses. Chromatography and spectroscopy are the analytical methods most used for the biodiesel characterization, but procedures based on physical properties are also available.Previously, a review on analytical methods used to evaluate biodiesel quality was written by Knothe. Due to the importance of this field, we made an update of Knothes’ review. Therefore, in this paper, we will describe new developments in biodiesel analyses and some references showed in Knothes’ paper. Specially, we will describe analytical methods used for quantification of glycerol, mono-, di-, triglycerides, methanol, water, Na, K, P, and steroids in biodiesel or along the transesterification reaction. Also, the determination of biodiesel content in blends and some physicochemical parameters are discussed. At the end, we will assess the available techniques and point out some improvements on analytical methods for biodiesel characterization.     

Montmorillonite-supported KF/CaO: a new solid base catalyst for biodiesel production

Biodiesel is an alternative to petroleum-derived diesel fuel; development of a high-efficiency base catalyst to be used in heterogeneous biodiesel production is still a challenge. In this paper, a novel solid base catalyst, KF- and CaO-supported montmorillonite (KCa/MMT) was successfully synthesized by a facile impregnation method, and used for producing biodiesel in transesterification of commercial soybean oil with methanol. The catalysts were characterized by X-ray diffraction, carbon dioxide temperature-programmed desorption and scanning electron microscopy. Effects of the parameters, such as the loading amount of KF, the amount of KCa/MMT, and the methanol to oil molar ratios, on the yield of biodiesel were investigated. A maximum biodiesel yield of 98 % was obtained under the optimal reaction conditions. The separated catalyst can be directly used in the next round of reactions and gave a satisfactory yield. Furthermore, analysis of the catalyst's tolerance to oil-containing water or free fatty acids, and a kinetic study were also carried out. Koros–Nowak tests were designed and conducted, and it was proven that the heat and mass transfer were not limited by the reaction rate.