生物柴油调合对其低温流动性能的改善

为了了解生物柴油中脂肪酸甲酯组成对其低温流动性能的影响,探索改善其流动性能的方法,以大豆油、花生油和牛油为原料合成了大豆油甲酯、花生油甲酯和牛油甲酯,测定了它们的脂肪酸甲酯组成和低温流动性能.结果表明,长碳链饱和脂肪酸甲酯的含量是影响生物柴油低温流动性能的主要因素.通过对混合生物柴油流动性能的测定,发现可以通过不同来源...     

柴油低温流动性改进剂的研制及性能评价：Ⅱ.柴油低温流动性 …

研究评价了本课题组合成的低温流动性改进剂蜡晶分散剂Ｍ分别与乙烯－醋酸乙烯酯共聚物、聚甲基丙烯酸高级酯之间的协同效应。结果表明：Ｍ组分与乙烯－醋酸乙烯酯共聚物复配使用时表现了良好的协同效应，Ｍ和乙烯－醋酸乙烯酯聚合物以及聚甲烯酸高级酯组成的三元复配体系的协同效应更强。Ｍ具有助降冷滤作用。研究结果还表明，协同作用取决于Ｍ组分的分子结构，其中烃基链的长短具有重要影响。     

柴油低温流动性改进剂的研制及性能评价：Ⅰ. 低温流动性改进？…

在分析胜利石化总厂０＃柴油和齐鲁石化０＃柴油的烃族组成、蜡碳分布的基础上,进行分子设计,研制出一种柴油低温流动性改进剂。它主要由具有一定粘度的三元共聚物组成,实验表明,这种柴油低温流动性改进剂能十分有效地提高胜利石化总厂０＃柴油的低温使用性能,而胜利石化０＃柴油对目前国内外其它低温流动性改进剂的感受性较差。     

锂-铝类水滑石催化大豆油酯交换制备生物柴油

采用共沉淀法制备了不同锂-铝比[n(Li)/n(Al)]的Li-Al类水滑石,经不同温度下焙烧得到复合氧化物;将复合氧化物作为大豆油与甲醇反应制备生物柴油的催化剂,考察了其对大豆油酯交换反应的催化性能.结果表明,n(Li)/n(Al)=13的类水滑石在400℃下焙烧得到的复合氧化物对大豆油酯交换反应具有极高的催化活性....     

柴油低温流动性改进剂的研制及性能评价 Ⅰ. 低温流动性改进剂对柴油的感受性

在分析胜利石化总厂 0 #柴油和齐鲁石化 0 #柴油的烃族组成、蜡碳分布的基础上 ,进行分子设计 ,研制出一种柴油低温流动性改进剂。它主要由具有一定粘度的三元共聚物组成。实验结果表明 ,这种柴油低温流动性改进剂能十分有效地提高胜利石化总厂 0 #柴油的低温使用性能 ,而胜利石化 0 #柴油对目前国内外其它低温流动性改进剂的感受性较差。     

使用流动改进剂柴油的低温流变性研究

研究了柴油在加入柴油低温流动改进剂前后的低温流变性能。结果表明：柴油的浊点与冷滤点之间的温度区间是柴油表观粘度的突跃范围,是解决柴油低温流动性的重点;自制的WW－1型柴油低温流动改进剂的加入降低了低温下柴油的表观粘度的改善了柴油的低温流变性能。     

生物柴油中脂肪酸甲酯的成分分析

以正二十烷为内标物,建立了一种简便、精确的定量分析生物柴油中脂肪酸甲酯含量的气相色谱方法.在实验条件下,各脂肪酸甲酯标准曲线的线性相关系数均在0.998 0以上,相对标准偏差为1.0%~5.3%.采用该方法分析生物柴油中脂肪酸甲酯含量的准确度和精密度较高,方法简单,重复性好,为生物柴油的成分分析和应用开发提供参考.     

气相色谱法在生物柴油生产工艺研究中的应用

综述了气相色谱法在生物柴油生产工艺研究中的应用,包括反应产物和生物柴油产品中脂肪酸甲酯含量和分布的测定,单脂肪酸甘油酯、二脂肪酸甘油酯和三脂肪酸甘油酯含量的测定,游离脂肪酸含量的测定以及微量甲醇含量的测定等。讨论了进样方式、色谱柱类型、硅烷化等因素对反应产物组成测定的影响;提出了一种采用双柱压力反吹的方式测定生物柴油产品中微量甲醇含量的方法：采用正丙醇作内标,甲醇与内标通过预切柱进入分析柱后,通过压力变化,将其余组分通过分流出口反吹出色谱系统;采用极性聚乙二醇色谱柱测定了8种不同植物油中脂肪酸甲酯的含量和分布。     

钙镁负载型固体碱催化剂制备生物柴油

固体碱催化剂;酯交换反应;脂肪酸甲酯;生物柴油     

低温下生物柴油的胶凝特性研究

利用流变仪在小振幅振荡剪切模式下对地沟油、花生油和大豆油生物柴油的胶凝特性进行了研究。结果表明,低温下生物柴油不仅具有冷却胶凝特性,还表现出明显的等温胶凝特性。分析了冷却速率和剪应力对地沟油生物柴油胶凝特性的影响。结果表明,静态降温时降温速率越大,生物柴油的胶凝温度越低,降温及恒温静置过程中同一温度下的胶凝结构越弱。相同降温速率下,生物柴油的胶凝结构和胶凝温度随剪应力的增加而降低,但经受不同剪应力作用的生物柴油恒温静置后胶凝结构相差不大。降温过程中施加的剪应力较小时,冷却胶凝结构随降温速率的增大而降低;剪应力较大时,冷却胶凝结构随降温速率的增大而加强。不管施加的剪应力多大,等温胶凝结构随降温速率的增大而加强。     

Structure and properties of partially epoxidized soybean oil

In the present study, the characteric-structure relationship of epoxidized soybean oils (ESO) with various degrees of epoxidation has been investigated. FTIR analysis was used to identify the relative extent of epoxidation of the samples during the epoxidation reaction. The viscosities of ESO were much higher than that of the raw oil, viscosity increased with degree of epoxidation. The viscous-flow activation energy of ESO was determined to be higher than that of the raw oil (20.72 to 77.93% higher). Thermogravimetry analysis (TG) of ESO was used to investigate the thermodynamic behavior of the samples. With increasing degree of epoxidation, the thermal stability of the samples initially decreased, then increased at the final reacting stage. Differential scanning calorimeter (DSC) indicated that the melting point of ESO was higher than that of soybean oil. Gel permeation chromatography (GPC) indicated the molecular mass of the samples increased initially, then decreased, with an increase in the extent of epoxidation.     

Curing behavior of epoxidized soybean oil with biobased dicarboxylic acids

In this study, we report the curing of ESO with biobased dicarboxylic acids (DCAs) with different carbon chain-lengths to synthesize fully sustainable polymers. Both non-isothermal and isothermal curing processes analysis indicated that the curing rate and activation energy decreased with increasing chain-length of DCAs. The optimum COOH/epoxy molar ratio is 0.7 for preparation of ESO/DCA cured product with maximum degree of crosslinking. Addition of 4-N, N-dimethylaminopyridine (DMAP) as a catalyst can efficiently accelerate the curing rate and reduce activation energy. We systemtically studied the effect of chain-length of DCAs on the physical properties of cured products, and found that with increase in chain-length of DCAs, the glass transition temperature of the cured ESO/DCA decreased, the tensile strength and Young's modulus increased while elongation at break decreased, due to the decreased crosslinking density resulted from the increased chain-length between crosslinking sites. All cured ESO/DCA showed excellent thermal stability with initial decomposition temperature of higher than 340 °C.     

Mechanical and thermal properties of epoxidized soybean oil plasticized polybutylene succinate blends

Epoxidized soybean oil (ESO) was blended as a novel plasticizer with polybutylene succinate (PBS) in a twin‐screw extruder. The effects of ESO on the mechanical and thermal properties of the PBS/ESO blends were investigated by means of tensile test, differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and scanning electronic microscope. ESO improved elongation at break for PBS, which increased and then decreased with the increase in ESO. Elongation at break reached a maximum of 15 times than that for pure PBS when the ESO loading was 5 wt%. The tensile strength and modulus for the blends were lower than those for pure PBS. Compared with pure PBS, the blends exhibited lower glass transition temperature, crystallization temperature, and melting temperature. The storage modulus and tan δ peaks for the blends were lower compared with that for pure PBS. ESO had very limited compatibility with PBS, and phase separation was observed when more ESO was added. Copyright © 2011 John Wiley & Sons, Ltd.     

Nutritional improvement of soybean oil via lipase-catalyzed interesterification

In order to decrease the content of linoleoyl moiety in soybean oil, soybean oil that contains 22.8% oleoyl, 54.8% linoleoyl, and 7.1% α-linolenoyl moieties as molar acyl moiety composition was interesterified in hexane with oleic acid or α-linolenic acid, using an immobilized sn-l,3-specific lipase (Lipozyme® IM) fromMucor miehei. The reactions were carried out in a batch reactor at 37°C in the following system: molar ratio of fatty acid to soybean oil = 1.0 ～ 6.0, 5.0 mL of hexane/500 μmol soybean oil, and 10.0 or 15.0 batch interesterification units of enzyme/500 μmol soybean oil. Under these reaction conditions, the rates of interesterification of acyl moieties in soybean oil were of the order: stearoyl > palmitoyl > linoleoyl > oleoyl > α-linolenoyl, and the reaction with oleic acid occurred without a significant loss of α-linolenoyl moiety. At the molar ratio of 3.0 and the reaction time of 6 h, triacylglycerols (TGs), which contain 50.8% oleoyl, 38.8% linoleoyl, and 5.4% α-linolenoyl moieties, were produced in the reaction with oleic acid; TGs that contain 13.5% oleoyl, 40.8% linoleoyl, and 40.4% α-linolenoyl moieties were obtained with α-linolenic acid. Approximately 86-88% of the interesterification of linoleoyl moiety, which occurred in 10 h, took place within 1 h.     

Optimization of alkaline transesterification of soybean oil and castor oil for biodiesel production

This article reports experimental data on the production of fatty acid ethyl esters from refined and degummed soybean oil and castor oil using NaOH as catalyst. The variables investigated were temperature (30–70°C), reaction time (1–3 h), catalyst concentration (0.5–1.5 w/wt%), and oil-to-ethanol molar ratio (1:3–1:9). The effects of process variables on the reaction conversion as well as the optimum experimental conditions are presented. The results show that conversions >95% were achieved for all systems investigated. In general, an increase in reaction temperature, reaction time, and in oil-to-ethanol molar ratio led to an enhancement in reaction conversion, whereas an opposite trend was verified with respect to catalyst concentration.     

Modified soybean oil as a reactive diluent: Synthesis and characterization

Soybean oil was modified in two steps: (1) conjugation of soybean oil and (2) Diels‐Alder addition with 3‐(trimethoxysilyl)propyl methacrylate, 2,2,2‐trifluoroethyl methacrylate and triallyl ether acrylate. The structures were characterized using ¹H NMR, ¹³C NMR, ¹³C‐¹H gradient heteronuclear single quantum coherence (gHSQC) NMR spectroscopy, and MALDI‐TOF mass spectrometry. The ¹³C‐¹H gHSQC NMR spectra helped confirm the formation of a cyclohexene ring in all reactions, indicating a Diels‐Alder addition. The diluent efficiency of modified soybean oil was evaluated in long oil alkyd formulation. Triallyl ether functionalized soybean oil resulted in the highest reduction in the viscosity of the alkyd formulations. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3045–3059     

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.     

熔盐热裂解大豆油的特性研究

以大豆油为原料,在ZnCl₂-KCl熔融盐体系中考察了进料速量、载气流量、反应温度及进料量对其热裂解的影响。采用气相色谱-质谱联用仪(GC-MS)表征生物油组成。结果表明,进料速量和载气流量主要通过改变大豆油的反应停留时间影响裂解效果。当进料速率为1.2 g/min及不通载气时,大豆油停留时间较长,裂解较充分;随着温度升高,生物油得率增大,含氧化合物含量及酸值上升;随着进料量增大,生物油得率稳定在70%左右,但脱羧效果有所下降。经过催化加氢,生物油性质得到了明显的改善,组分分布与0^#柴油分布大体相似。     

Kinetics of enzyme-catalyzed alcoholysis of soybean oil in n-hexane

This work investigated the production of fatty acid ethyl esters (FAEEs) from soybean oil using n-hexane as solvent and two commercial lipases as catalysts, Novozym 435 and Lipozyme IM. A Taguchi experimental design was adopted considering the variables temperature (35–65°C), addition of water (0–10 wt/wt%), enzyme (5–20 wt/wt%) concentration, and oil-to-ethanol molar ratio (1:3–1:10). It is shown that complete conversion in FAEE is achieved for some experimental conditions. The effects of process variables on reaction conversion and kinetics of the enzymatic reactions are presented for all experimental conditions investigated in the factorial design.