Analytical study for atomization of biodiesels and their blends in a typical injector: Surface tension and viscosity effects

This study presents analytical comparisons of atomization characteristics of 7 biodiesels and 17 binary and ternary blends with D1 and D2 at 80 °C, using a direct injection injector. The atomization of a genetically modified vegetable oil – Captex 355 – and its corresponding biodiesel were also studied. Results from statistical analysis showed that B100 coconut biodiesel had similar atomization characteristics to D2, because of its similar properties, i.e. density, surface tension and viscosity. No significant difference in drop size was observed for all B5 blends, and B20 blends and B100 biodiesels of palm, soybean, cottonseed, peanut and canola. It implies these stocks of biodiesels and their blends can be used in a DI engine with similar atomization characteristics. Ternary biodiesel blends, with ⩽10 wt.% petroleum diesel, can yield equal drop sizes as some binary blends with large quantities of D1 and D2. The ternary biodiesel blends are likely to reduce pollution from exhaust emissions better than the biodiesel blends with D1 or D2. Captex 355 biodiesel had the best atomization characteristics of all the fuels studied. The Sauter mean diameter (SMD) produced by this fuel was up to 13% and 25% smaller than that of D1 and D2, respectively. The Captex 355 biodiesel may be used as a base in binary or ternary biodiesel blends to achieve better atomization than D1 and D2 in diesel engines.     

麻疯树籽油生物柴油-0#柴油混合燃料与橡胶、塑料的兼容性

麻疯树籽油是制备生物柴油的优良原料油,由其制得的生物柴油具有良好的应用前景。为了分析和评价在运输、储存和使用过程中麻疯树籽油生物柴油与材料的相互影响,本文主要考察了4种橡胶和4种塑料分别与麻疯树籽油生物柴油-0#柴油混合燃料的相互作用及影响。试验结果表明：生物柴油混合燃料与材料接触28～56天后,其酸值和运动黏度仍满足国家标准要求;氟橡胶质量、硬度变化小,厚度的变化率小于18.00%,拉伸强度变化率小于?22.00%,有较好的耐甲酯性,而氯丁橡胶、三元乙丙橡胶及丁腈橡胶不能长期使用;生物柴油混合燃料对4种塑料厚度、质量的影响较小,其稳定性较好。     

Improving the cold flow properties of biodiesel from waste cooking oil by ternary blending with bio-based alcohols and diesel from direct coal liquefaction

The utilization and popularization of biodiesel are always limited by its poor cold flow properties. Both bio-based alcohol and diesel from direct coal liquefaction (DDCL) has potential to enhance the cold flow properties of biodiesel. In this study, ternary blends of waste cooking oil biodiesel (BWCO) with DDCL and bio-based ethanol (ET) or 1-butanol (BT) were conducted to improve the cold flow properties of biodiesel. The pour point (PP), cold filter plugging point (CFPP), and cloud point (CP) of BWCO-ET, BWCO-BT, and BWCO-DDCL binary blends, and BWCO-ET-DDCL and BWCO-BT-DDCL ternary blends were comparatively assessed. Ternary phase diagrams were also applied to analyze the blending effect of the three components on the cold flow properties of biodiesel. Results showed that both DDCL, ET, and BT can remarkably enhance the cold flow properties of BWCO. When the ternary blends contain 20 vol.% BWCO and less than 40 vol.% ET or BT, DDCL together with ET or BT exerted positive effects on enhancing the low-temperature flow properties of BWCO, especially on the CP and CFPP. For ternary blends in 20:10:70 blending ratio, BWCO-BT-DDCL exhibited the lowest PP, CFPP, and CP of −23, −19, and −17°C, respectively. The crystallization behavior and crystal morphology of blended fuels are also observed via a polarizing optical microscope, and find that DDCL together with BT in biodiesel can effectively retard the aggregation of large crystals and inhibit crystals growth.     

Pressure-volume-temperature properties for binary and ternary polymer solutions of poly(ethylene glycol), poly(propylene glycol), and poly(ethylene glycol methyl ether) with anisole

Pressure-volume-temperature properties were measured for polymer solutions of poly(propylene glycol) (PPG)+anisole, polymer blends of PPG+poly(ethylene glycol methyl ether) (PEGME), and the blends of PPG+PEGME and poly(ethylene glycol) (PEG)+PPG with anisole at temperatures from 298.15 to 348.15 K and pressures up to 50 MPa. The Tait equation represents accurately the pressure effect on the liquid densities over the entire pressure range. The excess volumes change from positive to negative as increasing the mole fraction of PPG in the binary systems of PPG+anisole and PPG+PEGME. The volumetric data of the related binary systems were correlated with the Flory-Orwoll-Vrij and the Schotte equations of state to determine the binary parameters. By using these determined binary parameters, both equations predicted the specific volumes of the polymer blends with anisole to average absolute deviations of better than 0.13%.     

硅钨酸在麻疯树油合成生物柴油中的应用研究

以麻疯树油与甲醇为原料,以硅钨酸为催化剂,通过酯交换反应制备生物柴油。考察了不同反应温度、反应时间、醇油摩尔比、催化剂质量分数等因素对生物柴油转化率的影响,并采用FT-IR和1H-NMR分别对催化剂进行了表征。研究结果表明：脱水后的硅钨酸具有较强的催化活性,其在反应温度为65℃、反应时间为3 h、醇油摩尔比为12∶1、催化剂质量分数为3.0%时,麻疯树油转化成生物柴油的转化率可达81.7%。     

An optimum biodiesel combination: Jatropha and soapnut oil biodiesel blends

Jatropha (Jatropha curcas) and soapnut (Sapindus mukorossi) oils are considered potential non-edible oil feedstocks for biodiesel production and present complementary fuel properties. Apparently, the poor oxidation stability of jatropha oil biodiesel and the high cold filter plugging point of soapnut oil biodiesel can be successfully improved to satisfy all biodiesel specifications at an optimum blending ratio. The optimum biodiesel combination was further blended with diesel at various volumetric percentages to evaluate the variations of fuel properties. The biodiesel–diesel blends up to B40 would show the satisfactory fuel properties.     

1-丁基-3-甲基咪唑磷酸二丁酯+甲醇/乙醇+水三元工质溶液混合焓的测量及预测

采用绝热量热法测量了由离子液体1-丁基-3-甲基咪唑磷酸二丁酯([bmim][DBP])分别与CH₃OH、C₂H₅OH和H₂O所组成的3个二元工质溶液体系[bmim][DBP](1)+ CH₃OH(2)/C₂H₅OH(2)/H₂O(2),以及2个三元工质溶液体系[bmim][DBP](1)+ CH₃OH(2)/C₂H₅OH(2)+ H₂O(3)在298.15 K和常压下的摩尔混合焓H_m^E。利用Gibbs-Helmholtz方程和NRTL活度系数模型,对每个二元溶液体系摩尔混合焓的实验数据进行关联,获得模型方程中的组分作用参数。摩尔混合焓的模型拟合值与实验值的平均相对偏差分别为1.81%、1.44%和0.72%。在此基础上预测了2个三元工质溶液体系的摩尔混合焓。结果表明:三元工质溶液体系的摩尔混合焓在实验浓度范围内均为负值,混合为放热过程。表明三元工质溶液具有成为吸收制冷循环新工质溶液的基本特征;采用NRTL模型预测2个三元溶液体系摩尔混合焓的计算值与实验值的平均相对误差分别为2.31%、2.49%。     

生物柴油全生命周期资源和能源消耗分析

针对以菜籽油、麻疯树油和地沟油为原料制取生物柴油过程,应用生命周期评价方法,对原料种植、收集运输、原料预处理、生物柴油生产、产品配送等子过程的土地资源占用、水资源和能源消耗进行了计算,并对能量消耗进行了参数敏感性分析. 结果表明,3种原料生产1 t生物柴油占用土地资源分别为13132, 3333和5 m2,水资源消耗分别为9063.55, 12306.62和1.97 m3,化石能源消耗分别为0.9, 0.67和0.25 MJ. 由于水资源消耗和土地占用主要源于种植环节,能源消耗主要发生在种植和转化环节,在我国适合以地沟油和麻疯树油为原料生产生物柴油. 开发耐旱、高产、高含油率的油料植物品种和新型高效酯交换反应催化剂及优化反应工艺是降低生物柴油全生命周期资源占用和能源消耗的有效措施.     

Combustion analysis of Jatropha, Karanja and Polanga based biodiesel as fuel in a diesel engine

Non-edible filtered Jatropha (Jatropha curcas), Karanja (Pongamia pinnata) and Polanga (Calophyllum inophyllum) oil based mono esters (biodiesel) produced and blended with diesel were tested for their use as substitute fuels of diesel engines. The major objective of the present investigations was to experimentally access the practical applications of biodiesel in a single cylinder diesel engine used in generating sets and the agricultural applications in India. Diesel; neat biodiesel from Jatropha, Karanja and Polanga; and their blends (20 and 50 by v%) were used for conducting combustion tests at varying loads (0, 50 and 100%). The engine combustion parameters such as peak pressure, time of occurrence of peak pressure, heat release rate and ignition delay were computed. Combustion analysis revealed that neat Polanga biodiesel that results in maximum peak cylinder pressure was the optimum fuel blend as far as the peak cylinder pressure was concerned. The ignition delays were consistently shorter for neat Jatropha biodiesel, varying between 5.9^° and 4.2^° crank angles lower than diesel with the difference increasing with the load. Similarly, ignition delays were shorter for neat Karanja and Polanga biodiesel when compared with diesel.     

麻疯树籽油生物柴油与0#柴油的混配性质

目前,生物柴油主要用于与石化柴油制成混配物使用。混配物的性质对储运、使用产生重要影响。研究了两种来源的麻疯树籽油与甲醇进行酯交换反应制备得到的生物柴油与0^#柴油混配物的密度、硫含量、运动黏度、冷滤点和闪点等性质。结果表明,混配物的密度随生物柴油体积分数增加呈线性增加;硫含量随生物柴油体积分数增加而线性减小;混配物的运动黏度可以根据生物柴油与石化柴油的密度、黏度及体积分数预测;混配物的闪点在生物柴油体积分数小于40％时随着生物柴油体积分数增加缓慢,在大于40％,特别是大于70％以后增加迅速。混配物的冷滤点相对麻疯树籽油生物柴油和0^#柴油的冷滤点无明显变化。     

1,2-丙二醇水溶液在不同温度下的超额摩尔体积黏度和热容

Experimental densities, viscosities and heat capacities at different temperatures were presented over the entire mole fraction range for the binary mixture of 1,2-propanediol and water. Density values were used in the determination of excess molar volumes, VE. At the same time, the excess viscosity was investigated. The values of VE and E were fitted to the Redlich-Kister equation. Good agreement was observed. The excess volumes are negative over the entire range of composition. They show an U-shaped-concentration dependence and decrease in absolute values with increase of temperature. Values of E are negative over the entire range of the composition, and has a trend very similar to that of VE . The analysis shows that at any temperature the specific heat of mixture is a linear function of the composition as x1 > 20%. All the extended lines intersect at one point. An empirical equation is obtained to calculate the specific heat to mixture at any composition and temperature in the experimental range.     

麻疯树籽油制备生物柴油的工艺研究

试验研究了乙醇钠催化下麻疯树籽油与乙醇进行酯交换反应制备生物柴油的工艺条件.通过正交试验和单因素试验发现,酯交换反应的最佳工艺条件为:催化剂用量为油重的1.5%,醇油物质的量比为15:1,反应温度为78℃,反应时间为120 min;在此反应条件下,橡胶籽油转化率为89.28%.     

正癸烷+正戊醇,+1-己醇,+庚醇二元混合物在293.15到363.15K和大气压力下的密度和粘度（英文）

Densities (ρ) and dynamic viscosities (η) for three binary mixtures of n-decane with 1-pentanol, 1-hexanol and 1-heptanol are presented at temperatures from 293.15 to 363.15 K and atmospheric pressure over the entire composition range. The density and viscosity are measured using a vibrating tube densimeter and a cylindrical Couette type rotating viscometer, respectively. Excess molar volumes (VE), viscosity deviations (Δη) and excess Gibbs energy of activation of viscous flow (ΔG*E) are calculated from the experimental measurements. Intermo-lecular and structural interactions are indicated by the sign and magnitude of these properties. Partial molar vol-umes and infinity dilution molar partial volumes are also calculated for each binary system. These results are correlated using Redlich–Kister type equations.     

脂肪酶催化非食用植物油制备生物柴油的过程优化

以麻疯树油、亚麻油、乌柏油为原料油,采用固定化脂肪酶Lipozyme TL IM,在3.0 g油、1 mL正己烷、醇油摩尔比为3.5∶1、固定化酶质量为油质量20%的条件下进行生物柴油的制备,通过脂肪酸甲酯产率和组成分析,以考察生物柴油制备的影响因素,进行反应时间优化.结果表明,酶的催化作用对脂肪酸组分不存在选择性,且...     

The specific gravity of biodiesel and its blends with diesel fuel

The specific gravities of biodiesel and 75, 50, and 20% blends with No. 1 and No. 2 diesel fuels were measured as a function of temperature from the onset of crystallization to 100°C. The results indicate that biodiesel and its blends demonstrate temperature-dependent behavior that is qualitively similar to the diesel fuels. The temperature dependence of the specific gravity for biodiesel and its blends was compared with the ASTM D 1250-80 procedure for the temperature correction of hydrocarbon fuels, and the procedure was found to provide accurate corrections. A blending equation was developed that allows the specific gravity of blends to be calculated from the specific gravities of the biodiesel and diesel fuels.     

2-甲基-3-丁烯-2-醇+直链一元醇二元体系的过量摩尔体积和表观摩尔体积298.15 K)

Excess molar volumes (Vm^E) of binary mixtures of 2-methyl-3-buten-2-ol[CH3C(OH)(CH3)CHCH2] with four 1-alcohols:methanol,ethanol,1-propanol and 1-butanol at 298.15K and atmospheric pressure are derived from density measurements with a vibrating-tube densimeter.All the excess volumes are negative in the systems over the entire composition range. The results are correlated with the Redlich-Kister equation.The effects of chain length of 1-alcohols on Vm^E are discussed.The apparent molar volumes of 2-methyl-3-buten-2-ol and 1-alcohols are calculated respectively.     

Jatropha curcas: A potential source for tomorrow' s oil and biodiesel

Greenhouse gas emission (GHG) is the driving force for global climate change. Deforestation accounts for over 20% of the world's GHG emission and leaves behind deforested areas. It is of utmost importance to revert these areas in a way that carbon is sequestered again. Jatropha curcas, a perennial tree or shrub, is capable of growing on such degraded land and eventually reclaim it. In addition to providing biodiesel of high quality it has several other uses of economic importance. There is an edible genotype of J. curcas that exclusively grows in Mexico. Fatty acid composition of both toxic and non‐toxic genotypes mirrors that of most conventional plant oils used for biodiesel production. Biodiesel produced from J. curcas oil meets all the requirements stipulated by the EU‐Standard EN‐14214. As J. curcas is still a wild plant, initiation of systematic selection and breeding programmes is a prerequisite for sustainable utilization of this plant for oil and biodiesel production.     

Density and Excess Molar Volume of Binary Mixtures ofp-Xylene＋Acetic Acid and o-Xylene＋Acetic Acid at Different Temperatures and Pressures

A new apparatus was designed with a thick-walled glass capillary, electric heater tube with red copper and heat preservation. The thick-walled glass capillary was used for its advantages of resistance to acid corrosion and pressure, and ease of observation. The experimental densities over the entire range of mole fraction for the binary mixture of p-xylene＋acetic acid and o-xylene＋acetic acid were measured using the new apparatus at temperatures ranging from 313.15K to 473.15K and pressure ranging from 0.20 to 2,0 MPa. The density values were used in the determination of excess molar volumes, W. The Redlich-Kister equation was used to fit the excess molar volume values, and the coefficients and estimate ot the standard error values were presented. The experimental resuits prove that the density measurement apparatus is successful.     

Comparative evaluation of performance and emission characteristics of jatropha, karanja and polanga based biodiesel as fuel in a tractor engine

Non-edible jatropha (Jatropha curcas), karanja (Pongamia pinnata) and polanga (Calophyllum inophyllum) oil based methyl esters were produced and blended with conventional diesel having sulphur content less than 10 mg/kg. Ten fuel blends (Diesel, B20, B50 and B100) were tested for their use as substitute fuel for a water-cooled three cylinder tractor engine. Test data were generated under full/part throttle position for different engine speeds (1200, 1800 and 2200 rev/min). Change in exhaust emissions (Smoke, CO, HC, NO_x, and PM) were also analyzed for determining the optimum test fuel at various operating conditions. The maximum increase in power is observed for 50% jatropha biodiesel and diesel blend at rated speed. Brake specific fuel consumptions for all the biodiesel blends with diesel increases with blends and decreases with speed. There is a reduction in smoke for all the biodiesel and their blends when compared with diesel. Smoke emission reduces with blends and speeds during full throttle performance test.     

Excess Molar Volume, Viscosity and Heat Capacity for the Binary Mixture of p-Xylene and Acetic Acid at Different Temperatures

Experimental densities, viscosities and heat capacities at different temperatures were presented over the entire range of mole fraction for the binary mixture of p-xylene and acetic acid. Density values were used in the determination of excess molar volumes, VE. At the same time, the excess viscosity and excess molar heat capacities were calculated. The values of VE, ηE and cpE were fitted to the Redlich-Kister equation. Good agreements were observed. The excess molar volumes are positive with a large maximum value located in the central concentration range. The excess viscosity has an opposite trend to the excess molar volume VE. ηE values are negative over the entire range of the mixture. The cure of dependence of cpE on concentration has a special shape. The molecular interaction between p-xylene and acetic acid is discussed.