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.     

Fast Biodiesel Production with One-Phase Reaction

The feasibility of fatty acid methyl ester (FAME) as a co-solvent used to increase the mass transfer between oil and methanol was investigated. FAME, as the co-solvent, does not require additional separation after the reaction because it is the end product of the reaction. To examine intermediate phenomena during the transesterification of soybean oil, the agitation speed was controlled at a slow rate. When the molar ratio of oil to methanol was 1:6 at 0.8wt.% of KOH to oil, oil was at the bottom layer, and methanol and the catalyst were at the top layer. Under the slow agitation process, the contact surface became initially darkened with the production of FAME and glycerol. After a few minutes, the entire top layer became dark. The top layer, containing methanol, KOH, FAME, and glycerol, fell to the bottom layer and then formed the one-phase system. When 0, 5, and 10 wt.% of FAME to oil was initially introduced to the reaction mixture, the FAME content rapidly increased with the FAME concentration level. After forming the one-phase system, the rate of increase of the FAME content was very slow. The time required for the formation of the one-phase system decreased with the amount of FAME and KOH and with temperature.     

Production and Characterization of Biodiesel from Tung Oil

The feasibility of biodiesel production from tung oil was investigated. The esterification reaction of the free fatty acids of tung oil was performed using Amberlyst-15. Optimal molar ratio of methanol to oil was determined to be 7.5:1, and Amberlyst-15 was 20.8wt% of oil by response surface methodology. Under these reaction conditions, the acid value of tung oil was reduced to 0.72mg KOH/g. In the range of the molar equivalents of methanol to oil under 5, the esterification was strongly affected by the amount of methanol but not the catalyst. When the molar ratio of methanol to oil was 4.1:1 and Amberlyst-15 was 29.8wt% of the oil, the acid value decreased to 0.85mg KOH/g. After the transesterification reaction of pretreated tung oil, the purity of tung biodiesel was 90.2wt%. The high viscosity of crude tung oil decreased to 9.8mm²/s at 40 °C. Because of the presence of eleostearic acid, which is a main component of tung oil, the oxidation stability as determined by the Rancimat method was very low, 0.5h, but the cold filter plugging point, −11 °C, was good. The distillation process did not improve the fatty acid methyl ester content and the viscosity.     

Enzymatic Synthesis of Biodiesel via Alcoholysis of Palm Oil

The enzymatic alcoholysis of crude palm oil with methanol and ethanol was investigated using commercial immobilized lipases (Lipozyme RM IM, Lipozyme TL IM). The effect of alcohol (methanol or ethanol), molar ratio of alcohol to crude palm oil, and temperature on biodiesel production was determined. The best ethyl ester yield was about 25 wt.% and was obtained with ethanol/oil molar ratio of 3.0, temperature of 50 °C, enzyme concentration of 3.0 wt.%, and stepwise addition of the alcohol after 4 h of reaction. Experiments with 1 and 3 wt.% of KOH and 3 wt.% of MgO were carried out to compare their catalytic behavior with the enzymatic transesterification results. The commercial immobilized lipase, Lipozyme TL IM, showed the best catalytic performance.     

多频超声反应槽连续强化酸化油酯交换制备生物柴油研究

以平均酸值高达33.07 mgKOH/g不可食用的廉价酸化油为原料,利用自行设计的多频超声溢流槽连续强化酯交换反应生物柴油生产装置,先后经预酯化、酯交换两步反应,高效、低耗的制备生物柴油。主要考察了室温下物料流量(停留时间)、超声功率、超声频率及组合、KOH用量、醇油物质的量比对酯交换反应的影响及单位产品能耗。结果表明,多频组合超声辐射比单频更有利于生物柴油的制备;预酯化后的油料在流量为25 L/h(物料停留时间为54 min),催化剂(KOH)用量为1.2%(质量分数),醇油物质的量比为6∶1和各反应槽功率为200 W的条件下,甲酯产率达96.83%。50 L废弃酸化油能制得符合国标GB19147—2009的生物柴油48L,整个生物柴油制备过程总耗时和总耗电量仅为8.667 h、5.42 kWh。     

Transesterification of palm oil using supercritical methanol with co-solvent HCFC-141b

The transesterification of palm oil in supercritical methanol has been investigated without using any catalyst. HCFC-141b was used as co-solvent to reduce the molar ratio of methanol to palm oil under the milder conditions. The reaction was carried out in a flow-type tubular reactor. The residence time was fixed at 40 min. When the molar ratio of methanol to palm oil was set to 20:1 at 325 °C and 35 MPa, the optimum molar ratio of methanol to co-solvent was found to be 20:1. Addition of HCFC-141b increased FAME production even at the lower molar ratio of methanol to palm oil. In addition, a similar FAME content was obtained under the milder conditions (5 MPa lower pressure) compared with conditions without co-solvent at higher pressure. The role of HCFC-141b in the transesterification reaction under supercritical conditions was investigated.     

棉籽现场碱催化转酯化联产生物柴油和无毒棉粕

通过棉籽现场碱催化转酯化联产生物柴油和无毒棉粕,考察了棉仁中水的质量分数、粒径对产物中脂肪酸甲酯（FAME）的质量分数和棉粕中游离棉酚（FG）质量分数的影响;对反应过程中的醇油摩尔比、反应时间、催化剂用量、反应温度进行了单因素和正交实验考察。实验得到的反应适宜条件为,棉仁含水量在1.92%左右,棉仁粒径小于0.335mm,反应醇油摩尔比135∶1,反应3h,甲醇中氢氧化钠浓度0.10mol/L,反应温度30℃。在上述反应条件下,反应产物中甲酯的质量分数可达97%,棉粕中游离棉酚的质量分数为0.031%,低于FAO规定的国际标准。     

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 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.     

Clean synthesis of biodiesel over solid acid catalysts of sulfonated mesopolymers

FDU-15-SO₃H, a solid acid material prepared from the sulfonation of FDU-15 mesoporous polymer, has been demonstrated to serve as an efficient catalyst in the esterification of palmitic acid with methanol as well as in the transesterification of fatty acid-edible oil mixture. FDU-15-SO₃H achieved an acid conversion of 99.0% when the esterification was carried out at 343 K with a methanol/palmitic acid molar ratio of 6:1 and 5 wt% catalyst loading. It was capable of giving 99.0% yield of fatty acid methyl esters (FAME) when the transesterification of soybean oil was performed at 413 K and the methanol/oil weight ratio of 1:1. FDU-15-SO₃H was further applied to the transesterification/esterification of the oil mixtures with a varying ratio of soybean oil to palmitic acid, which simulated the feedstock with a high content of free fatty acids. The yield of FAME reached 95% for the oil mixtures containing 30 wt% palmitic acid. This indicated the sulfonated mesopolymer was a potential catalyst for clean synthesis of fuel alternative of biodiesel from the waste oil without further purification.     

Alkali Hydrothermal Synthesis of Na0.1Ca0.9TiO3 Nanorods as Heterogeneous Catalyst for Transesterification of Camelina Sativa Oil to Biodiesel

Orthorhombic perovskite Na_0.1Ca_0.9TiO₃ nanorods were synthesized at low calcination temperature via alkali hydrothermal synthesis. The synthesized nanorods exhibits a square based prism morphology, with a width and length of 200–500 nm and 2–3 μm respectively. The structural, textural and basic characteristics of the catalyst were examined by SEM, TEM, XRD and BET. The growth direction of the nanorods was confirmed to be along the long symmetry [110] zone axis and the exterior surfaces are found to be polar (110) and (002) with either Ti or Ca exposed in those facets. The catalytic activity of the nanorods was investigated for the transesterification of the low-input Camelina Sativa oil and methanol to give the fatty acid methyl ester (FAME). Effects of important reaction parameters such as methanol to oil molar ratio, catalyst dosage, reaction temperature and reaction time on oil conversion were examined. Optimized biodiesel yield of 93 % was achieved with catalyst dosage of 6 % w/w, methanol to oil molar ratio of 36:1 at reaction temperature of 60 °C for 8 h.     

Batch (one- and two-stage) production of biodiesel fuel from rapeseed oil

Biodiesel fuel is an alternative and renewable energy source, which may help to reduce air pollution, as well as our dependence on petroleum for energy. Several processes have already been developed for the production of biodiesel. Alkali-catalyzed transesterification with short-chain alcohols, for example, generates high yields of methyl esters in short reaction times. In this study, we have evaluated the efficacy of batch (one- and two-stage) transesterification of rapeseed oil in the production of rapeseed methyl ester. The conversion of rapeseed oil exhibited similar reaction patterns and yields in 30- and 1-L reaction systems. Approximately 98% of the rapeseed oil was converted at 400 rpm within 20 min, under the following conditions: 1% (w/w) KOH, 1ratio10 methanol molar ratio, and at 60 degrees C. In the 30-L, two-stage transesterification process, approx 98.5% of the rapeseed oil was converted at a 1ratio4.5 molar ratio and 1% (w/w) KOH at 60 degrees C for 30 min (first reaction condition), and at a 1ratio1 molar ratio and 0.2% (w/w) KOH at 60 degrees C for 30 min (second reaction condition).     

Biodiesel fuel production by the transesterification reaction of soybean oil using immobilized lipase

The enzymatic alcoholysis of soybean oil with methanol and ethanol was investigated using a commercial, immobilized lipase (Lipozyme RMIM). The effect of alcohol (methanol or ethanol), enzyme concentration, molar ratio of alcohol to soybean oil, solvent, and temperature on biodiesel production was determined. The best conditions were obtained in a solvent-free system with ethanol/oil molar ratio of 3.0, temperature of 50 degrees C, and enzyme concentration of 7.0% (w/w). Three-step batch ethanolysis was most effective for the production of biodiesel. Ethyl esters yield was about 60% after 4 h of reaction.     

Comparison and optimisation of biodiesel production from <Emphasis Type="Italic">Jatropha curcas</Emphasis> oil using supercritical methyl acetate and methanol

In this study, biodiesel has been successfully produced by transesterification using non-catalytic supercritical methanol and methyl acetate. The variables studied, such as reaction time, reaction temperature and molar ratio of methanol or methyl acetate to oil, were optimised to obtain the optimum yield of fatty acid methyl ester (FAME). Subsequently, the results for both reactions were analysed and compared via Response Surface Methodology (RSM) analysis. The mathematical models for both reactions were found to be adequate to predict the optimum yield of biodiesel. The results from the optimisation studies showed that a yield of 89.4 % was achieved for the reaction with supercritical methanol within the reaction time of 27 min, reaction temperature of 358°C, and methanol-to-oil molar ratio of 44. For the reaction in the presence of supercritical methyl acetate, the optimum conditions were found to be: reaction time of 32 min, reaction temperature of 400°C, and methyl acetate-to-oil molar ratio of 50 to achieve 71.9 % biodiesel yield. The differences in the behaviour of methanol and methyl acetate in the transesterification reaction are largely due to the difference in reactivity and mutual solubility of Jatropha curcas oil and methanol/methyl acetate.     

废茶油的精制及其合成生物柴油的研究

本文以废茶油为原料,经过脱胶脱酸等预处理后与甲醇进行酯交换反应制取生物柴油.探讨了反应时间、反应温度、醇-油摩尔比和催化剂用量等因素对废茶油-甲醇酯交换反应的影响,并且采用正交实验优化合成条件,确定了反应的最佳操作条件以及影响反应的关键因素.研究结果表明,酯交换反应进行的最佳反应条件为:醇油摩尔比为25:1、催化剂用量为油重的1.0%、反应时间为30min、反应温度为60℃,茶油酸甲酯产率77.34%.     

Batch (one- and two-stage) production of biodiesel fuel from rapeseed oil

Biodiesel fuel is an alternative and renewable energy source, which may help to reduce air pollution, as well as our dependence on petroleum for energy. Several processes have already been developed for the production of biodiesel. Alkali-catalyzed transesterification with short-chain alcohols, for example, generates high yields of methyl esters in short reaction times. In this study, we have evaluated the efficacy of batch (one- and two-stage) transesterification of rapeseed oil in the production of rapeseed methyl ester. The conversion of rapeseed oil exhibited similar reaction patterns and yields in 30- and 1-L reaction systems. Approximately 98% of the rapeseed oil was converted at 400 rpm within 20 min, under the following conditions: 1% (w/w) KOH, 1∶10 methanol molar ratio, and at 60°C. In the 30-L, two-stage transesterification process, approx 98.5% of the rapeseed oil was converted at a 1∶4.5 molar ratio and 1% (w/w) KOH at 60°C for 30 min (first reaction condition), and at a 1∶1 molar ratio and 0.2% (w/w) KOH at 60°C for 30 min (second reaction condition).     

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.     

Fatty acid methyl ester production from acid oil using silica sulfuric acid: Process optimization and reaction kinetics

Conversion of high free fatty acids (FFA) containing acid oil (AO) to fatty acid methyl esters (FAME) using silica sulfuric acid (SSA) as a solid acid catalyst was investigated. Process parameters such as reaction temperature, reaction time, catalyst loading, and methanol to oil molar ratio were optimized using the Taguchi orthogonal array method. Maximum FFA conversion (97.16 %) was achieved under the optimal set of parameter values viz. 70°C, 4 mass % catalyst loading, and 1: 15 oil to methanol molar ratio after 90 min. SSA was reused three times successfully without a significant loss in activity. Biodiesel produced from AO met the international biodiesel standards. Determination of kinetic parameters proved that the experimental results fit the pseudo first order kinetic law.     

Production of Tung Oil Biodiesel and Variation of Fuel Properties During Storage

The crude Tung oil with 4.72?mg KOH/g of acid value (AV) was converted by direct transesterification, and the reaction mixture was quantified. The phase distribution data showed that 38.24% of excess methanol, 11.76% of KOH, 10.13% of soap and 4.36% of glycerol were in the biodiesel phase; 0.35% of biodiesel dissolved in the glycerol phase. Tung oil biodiesel as well as its blends with 0(#) diesel was investigated under different storage conditions. The results indicated that higher temperature greatly influenced the storage stability, especially when the volume fraction of Tung oil biodiesel is increased in the blends.     

酸化油固定床酶法合成生物柴油研究

酸化油是油脂工作中以皂脚、油脚经酸化处理得到的产品.它的主要成份是游离脂肪酸及中性油,是生产脂肪酸的重要原料,但生产过程中有水解废水的产生,若将其直接排放,既污染了环境又浪费了资源.