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1.
Microwave assisted transesterification of rapeseed oil 总被引:2,自引:0,他引:2
Rapeseed is one of the important vegetable oil sources for biodiesel production due to its high oil content (around 40%). In this study rapeseed oil was converted to biodiesel by transesterification using microwave heating. Experiments were carried out in the presence of two different alkali catalysts which are sodium hydroxide and potassium hydroxide. Effects of various reaction parameters such as catalyst ratio, reaction temperature and time were investigated. Mono-, di- and triglyceride content of biodiesel were determined by gas chromatography analysis. Yield and purity (ester content) percentages of biodiesel were specified in weight, which are 88.3–93.7% and 87.1–99.4%, respectively. The results indicated that microwave heating has effectively increased the biodiesel yield and decreased the reaction time. 相似文献
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This paper deals with the hydroprocessing of rapeseed oil representing a perspective technological way for production of biocomponents in diesel fuel range. Rapeseed oil was hydroprocessed at various temperatures (260-340 °C) under a pressure of 7 MPa in a laboratory flow reactor. Three Ni-Mo/alumina hydrorefining catalysts were used. Reaction products were analyzed using several gas-chromatographic methods. Reaction products contained water, hydrogen-rich gas and organic liquid product (OLP). The main components of OLP were identified as C17 and C18n-alkanes and i-alkanes. At a low reaction temperature, OLP contained also free fatty acids and triglycerides. At reaction temperatures higher than 310 °C, OLP contained only hydrocarbons of the same nature as hydrocarbons present in diesel fuel. Influence of reaction temperature and catalyst on the composition of reaction products is discussed. 相似文献
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Transesterification of rapeseed oil in the presence of basic zeolites and related solid catalysts 总被引:8,自引:1,他引:7
Elisabeth Leclercq Annie Finiels Claude Moreau 《Journal of the American Oil Chemists' Society》2001,78(11):1161-1165
The transesterification of rapeseed oil with methanol was performed by reflux of methanol over cesium-exchanged NaX faujasites,
mixed magnesium-aluminum oxides, magnesium oxide, and barium hydroxide for different methanol-to-oil ratios. Over cesium-exchanged
NaX faujasites and mixed magnesium-aluminum oxides, a long reaction time and a high methanol-to-oil ratio are required to
achieve both high oil conversion and high yields in methyl esters. However, over a 300 m2/g magnesium oxide, methanol-to-oil ratios and reaction times are significantly reduced to obtain both high oil conversion
and high yield in the methyl esters, particularly when the hydroxide precursor is calcined at 823 K. Finally, preliminary
results with other basic solids such as barium hydroxide have shown a very high activity and a very high yield in esters.
This catalyst is particularly effective since, for a methanol-to-oil ratio of 6, at reflux of methanol and after a reaction
time of only 1 h, the oil conversion is about 80% with a nearly quantitative ester molar fraction.
Part of this work was presented at the 91st AOCS Annual Meeting, San Diego, California, April 2000. 相似文献
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In this paper response surface methodology (RSM) was used to study the transesterification reaction of rapeseed oil for biodiesel production. The three main factors that drive the conversion of triglycerides into fatty acid methyl esters (FAME) were studied according to a full factorial design at two levels. These factors were catalyst concentration (KOH), temperature and reaction time. The range investigated for each factor was selected taking into account the process of Fox Petroli S.p.A. Analysis of variance (ANOVA) was used to determine the significance of the factors and their interactions which primarily affect the first of the two transesterification stages. This analysis evidenced the best operating conditions of the first transesterification reaction performed at Fox’s plant: KOH concentration 0.6% w/w, temperature 50 °C and reaction time 90 min with a CH3OH to KOH ratio equal to 60. Three empirical models were derived to correlate the experimental results, suitable to predict the behavior of triglyceride, diglyceride and monoglyceride concentration. These models showed a good agreement with the experimental results, demonstrating that this methodology may be useful for industrial process optimization. 相似文献
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预酯化-酯交换法利用餐饮废油脂制备生物柴油 总被引:1,自引:0,他引:1
以高酸值餐饮废油脂和乙醇为原料,采用预酯化-酯交换法制备生物柴油。第一步为预酯化反应,控制反应温度为70℃,最佳条件为:催化剂加入量为4%,反应时间为90min,带水剂加入量为10%,乙醇加入量控制在醇酸摩尔比为6∶1,可使油脂酸值降至4mg KOH·g-1以下,满足酯交换反应要求。第二步为酯交换反应,最佳条件是:醇油摩尔比为8∶1,碱性催化剂加入量为0.8%,反应温度为70℃,反应时间为30min。本方法具有反应时间短、转化率高,反应条件温和,清洁环保等优点。 相似文献
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Y. -Y. Linko M. Lämsä A. Huhtala P. Linko 《Journal of the American Oil Chemists' Society》1994,71(12):1411-1414
Lipase-catalyzed transesterification (alcoholysis) of lowerucic acid rapeseed oil and 2-ethyl-1-hexanol without an additional
organic solvent was studied in stirred batch reactors. Of a number of commercially available enzymes investigated, the best
results were obtained with aCandida rugosa lipase. The optimal transesterification conditions were an oil/alcohol molar ratio of 1∶2.8, a minimum of 1.0% (w/w) added
water, and with a temperature of 37–55°C. Under the optimal conditions, a nearly complete conversion was obtained in one hour
with 14.6% (w/w) lipase, whereas 0.3% (w/w) lipase required 10 h for similar results. The enzyme was inactivated at 60°C. 相似文献
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选用了非食用油麻疯果油为原料,以氢氧化钠、氢氧化钾、甲醇钠为催化荆,通过酯交换法制取生物柴油,研究表明最适宜工艺条件为:醇油比6:1,反应温度60℃,反应时间80min,搅拌强度为600 r/min,催化剂用量为1.2%,转化率达到97%以上,且生物柴油各项理化指标均符合美国和德国测试标准.且从麻疯果的种植到生物柴油的生产整个产业链出发,其原料成本更低,经济效益更大,体现了不与粮争地的优势. 相似文献
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This paper presents the results of engine tests of biodiesels obtained by transesterification of palm oil and rapeseed oil and with fossil diesel fuel as a reference. The analysis is focused on the determination of the ignition delay and on obtaining a predictive correlation for it. The experiments show no significant difference in in-cylinder pressures at injection timing for each fuel. With biodiesel slightly lower peak cylinder pressures were observed for most engine conditions. Palm oil and rapeseed oil biodiesel gave shorter ignition delay than fossil diesel fuel due to the higher cetane number for the biodiesels. The ignition delay data were correlated as a function of the equivalence ratio, the mean cylinder pressure and mean temperature over the ignition delay interval. A comparison is made with other available correlations. The ignition delay values estimated by the new correlations are in good agreement with the experiments. 相似文献
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Fuel properties of hydroprocessed rapeseed oil 总被引:1,自引:0,他引:1
This paper deals with the hydroprocessing of rapeseed oil as a source of hydrocarbon-based biodiesel. Rapeseed oil was hydroprocessed in a laboratory flow reactor under four combinations of reaction conditions at temperatures 310 and 360 °C and under hydrogen pressure of 7 and 15 MPa. A commercial hydrotreating Ni-Mo/alumina catalyst was used. Reaction products contained mostly n-heptadecane and n-octadecane accompanied by low concentrations of other n-alkanes and i-alkanes. Reaction product obtained at 360 °C and 7 MPa was blended into mineral diesel fuel in several concentration levels ranging from 5 to 30 wt.%. It was found, that most of the standard parameters were similar to or better than those of pure mineral diesel. On the other hand, low-temperature properties were worse, even after addition of high concentrations of flow improvers. 相似文献
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碳酸根型镁铝复合氢氧化物的合成和表征及其催化性能 总被引:8,自引:0,他引:8
以恒定pH值共沉淀法合成碳酸根型镁铝水滑石,用XRD、IR、TG-DTA和SEM等手段进行表征。XRD衍射表明,Mg与Al物质的量比为1∶1、3∶1、4∶1和6∶1的合成物均有水滑石结构。热重-差热分析(TG-DTA)显示,水滑石有两个吸热峰值:第一吸收峰值在200~250 ℃, 第二吸热峰值在400~450 ℃,最大损失重量在2780%~33.41%。SEM分析可知,样品呈层状、棒状、针状和蜂窝状等结构。并对镁铝复合氢氧化物作为催化剂用于生物柴油制备作了研究。结果表明,Mg与Al物质的量比为3∶1的水滑石可使甲酯收率达到90%左右,且可重复使用。产品达到德国生物柴油质量标准。 相似文献
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用棉籽油制备生物柴油 总被引:16,自引:0,他引:16
采用棉籽油为原料连续化生产生物柴油,研究了工艺及设备的设计。由棉籽油与甲醇在催化剂NaOH存在下由酯交换反应制得生物柴油。在优化条件下反应50 min,转化率达到99%。生产的生物柴油,各项指标与天然柴油相似。其各项燃烧指标优于或与普通柴油相仿,满足欧洲Ⅱ排放标准。 相似文献
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Response surface methodology (RSM) based on central composite design (CCD) was used to optimize the three important reaction variables — methanol/oil molar ratio (x1), reaction time (x2) and amount of catalyst (x3) for production of biodiesel from palm oil using KF/ZnO catalyst. Based on the CCD, a quadratic model was developed to correlate the reaction variables to the biodiesel yield. From the analysis of variance (ANOVA), the most influential factor on the experimental design response was identified. The predicted yield after process optimization was found to agree satisfactory with the experimental value. The optimum conditions for biodiesel production were found as follows: methanol/oil ratio of 11.43, reaction time of 9.72 h and catalyst amount of 5.52 wt%. The optimum biodiesel yield was 89.23%. 相似文献
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Analysis of target volatile compounds related to fishy off‐flavor in heated rapeseed oil: A comparative study of different headspace techniques 下载免费PDF全文
Lilia Sghaier Jérôme Vial Patrick Sassiat Didier Thiebaut Mickaël Watiez Sylvie Breton Douglas N. Rutledge Christophe B.Y. Cordella 《European Journal of Lipid Science and Technology》2016,118(6):906-918
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Babak Salamatinia 《Fuel Processing Technology》2010,91(5):441-448
The use of ultrasonic processor in the heterogeneous transesterification of palm oil for biodiesel production has been investigated. Response surface methodology was employed to statistically evaluate and optimize the biodiesel production process catalyzed by two alkaline earth metal oxide catalysts i.e. BaO and SrO. SEM, surface analysis, AAS analysis and the Hammett indicator methods were used for characterization of the catalysts. Four different variables including reaction time (10-60 min), alcohol to oil molar ratio (3:1-15:1), catalyst loading (0.5-3.0 wt.%) and ultrasonic amplitude (25-100%) were optimized. Mathematical models were developed and used to predict the behavior of the process. The models were able to accurately predict the biodiesel yield with less than 5% error for both catalysts. The basic strength of the catalysts was the main reason of their high activities. This study confirmed that the ultrasonic significantly improved the process by reducing the reaction time to less than 50 min and the catalyst loading to 2.8 wt.% to achieve biodiesel yields of above 95%. The optimum alcohol to oil ratio was found to be at 9:1 while the best amplitudes were ∼ 70 and ∼ 80% for the BaO and SrO catalysts, respectively. 相似文献