Fuel Properties of Biodiesel/Ultra-Low Sulfur Diesel (ULSD) Blends

Biodiesel is an alternative fuel and fuel extender easily derived from vegetable oil or animal fat. In 2006, the US Environmental Protection Agency mandated that maximum sulfur content of diesel fuels be reduced to 15 ppm to protect catalysts employed in exhaust after-treatment devices. Processing to produce this ultra-low sulfur petrodiesel (ULSD) alters fuel lubricity, density, cold flow, viscosity, and other properties. Consequently, there is a need to develop a better understanding of the basic fuel properties of biodiesel/ULSD blends. This work evaluates the effects of biodiesel volumetric blend ratio (V _BD) on cloud point (CP), kinematic viscosity (ν), specific gravity (SG), and refractive index (RI) of blends with petrodiesel. Properties measured for various blends of methyl esters of soybean oil (SME) and used cooking oil (UCOME) in ULSD were compared with those for blends with low sulfur (≤500 ppm) petrodiesel fuel (LSD). With respect to increasing V _BD, CP and SG increased and RI decreased with each parameter demonstrating a linear correlation. In contrast, ν showed a curvilinear relationship with respect to increasing V _BD. Calibration curves were derived from regression analyses to determine V _BD in biodiesel/ULSD blends from measurements of each individual property. While the models had generally high coefficients of regression (R ² > 0.986), SG models were most accurate for predicting V _BD to within 1.3 vol%.     

棉籽油制备生物柴油的研究概况

我国棉籽油原料充足,由棉籽油制备生物柴油具有广阔的发展前景。文章综述了酯交换反应中的酸、碱、酶、超临界法在棉籽油制备生物柴油中的研究概况。     

Sensitivity of Diesel Particulate Material Emissions and Composition to Blends of Petroleum Diesel and Biodiesel Fuel

A number of investigations have examined the impact of the use of biodiesel on the emissions of carbon dioxide and regulated emissions, but limited information exists on the chemical composition of particulate matter from diesel engines burning biodiesel blends. This study examines the composition of diesel particulate matter (DPM) emissions from a commercial agriculture tractor burning a range of biodiesel blends operating under a load that is controlled by a power take off (PTO) dynamometer. Ultra-low sulfur diesel (ULSD) fuel was blended with soybean and beef tallow based biodiesel to examine fuels containing 0% (B0), 25% (B25), 50% (B50), 75% (B75), and 100% (B100) biodiesel. Samples were then collected using a dilution source sampler to simulate atmospheric dilution. Diluted and aged exhaust was analyzed for particle mass and size distribution, PM_2.5 particle mass, PM_2.5 organic and elemental carbon, and speciated organic compounds. PM_2.5 mass emissions rates for the B25, B50, and B75 soybean oil biodiesel mixtures had 20%–30% lower emissions than the petroleum diesel, but B100 emissions were about 40% higher than the petroleum diesel. The trends in mass emission rates with the increasing biodiesel content can be explained by a significant decrease in elemental carbon (EC) emissions across all blending ranges and increasing organic carbon (OC) emissions with pure biodiesel. Beef tallow biodiesel blends showed similar trends. Nevertheless, it is important to note that the study measurements are based on low dilution rates and the OC emissions changes may be affected by ambient temperature and different dilution conditions spanning micro-environments and atmospheric conditions. The results show that the use of biodiesel fuel for economic or climate change mitigation purposes can lead to reductions in PM emissions and a co-benefit of EC emission reductions. Detailed speciation of the OC emissions were also examined and are presented to understand the sensitivity of OC emissions with respect to biodiesel fuel blends.

Copyright 2012 American Association for Aerosol Research     

乙醇柴油混合燃料的试验研究

对含5％～15％无水乙醇与柴油的混合燃料进行了实验研究。结果表明，在较高环境温度(18℃以上)及无水的情况下，可以不用助溶剂，形成稳定期较长的E5及E10。添加助溶剂可以使E10及E15在较低温度下保持稳定不分层。E10及E15的理化性质与普通柴油的性质较接近，在不改动柴油机的情况下，使用E10及E15，动力性能下降幅度不大，质量比油耗增加不多。驾驶员对使用E10的车辆性能表示满意，排气烟度有明显的改善。     

Biodiesel/Diesel Blends Classification with Respect to Base Oil Using NIR Spectrometry and Chemometrics Tools

In this work, rapid and non-destructive methodology is proposed for screening of biodiesel/diesel blends with respect to the base oil, using near infrared spectroscopy and multivariate data analysis, since for both pure biodiesel and blends, the biodiesel/diesel are targets for tampering. Blends of diesel with cotton, sunflower and soybean oils were employed in this study. Two approaches were evaluated in the building of the classification model, using full-spectrum Soft Independent Modelling of Class Analogy (SIMCA), and Principal Component Analysis–Linear Discriminant Analysis (PCA–LDA). The other approaches were the use of variable selection employing Genetic Algorithm (GA), Successive Projection Algorithm (SPA) and Stepwise all coupled with the LDA model. The results showed which preprocessed NIR spectra and chemometrics are a viable alternative the conventional methods that involve the consumption of large volumes of reagents. Multivariate data analysis methods using selected variables showed a better performance than the methods using a full spectrum.     

The Effect of Branched-Chain Fatty Acid Alkyl Esters on the Cold-Flow Properties of Biodiesel

Biodiesel (fatty acid methyl esters [FAME]) is produced from various fats, oils, and greases (FOG) using catalytic transesterification with methanol. These fuels have poor cold-flow properties depending on the fatty acid (FA) composition of the parent FOG. Improving the cold-flow properties of biodiesel will enhance its prospects for use during cooler months in moderate temperature climates. This work is a study on the use of skeletally branched-chain alkyl esters (BCAE) composed of the isopropyl, n-butyl, and 2-ethylhexyl esters of iso-oleic acid isomers (iPr-iOL, nBu-iOL, and 2EH-iOL). These BCAE additives were tested in blends with linear-FAME (L-FAME) derived from soybean oil (SME), lard (LME), tallow (TME), and sewage scum grease (SGME). Binary L-FAME/SME admixtures were also studied. Admixtures were tested for the effects of the additives on cloud point (CP), pour point (PP), and kinematic viscosities at standard (ν⁴⁰ = 40 °C) and low temperatures (T_L) = CP + 5 °C (ν^L). Although the BCAE additives were more effective than SME, relatively large additive concentrations (y_Add) were needed to depress CP and PP by more than 2 °C. Admixtures with high concentrations of BCAE additive had ν⁴⁰ > 6.0 mm² s⁻¹, the maximum limit in ASTM fuel specification D 6751. While the iPr-iOL and nBu-iOL additives may be blended at concentrations up to y_Add = 0.50, 2EH-iOL should not exceed y_Add = 0.28 in LME, 0.31 in SGME, 0.35 in TME, or 0.41 in SME to avoid driving the admixture out of specification. Some anomalies observed in the results at low y_Add for SGME/BCAE admixtures were speculated to have been affected by the low-temperature rheology of SGME.     

棉籽油酯交换法制备生物柴油及其燃烧性能的研究

实验是通过用棉籽油为原料,KOH做催化剂制备生物柴油的.用气相色谱分析方法,通过对反应温度、醇油摩尔比、催化剂的量等的研究得出反应的最佳条件:温度60℃、醇油摩尔比6∶1、KOH浓度为1.0%,转化率可达97.8%.通过对比实验,研究燃烧棉籽油制生物柴油和普通柴油对发动机动力性、经济性和排放特性的影响.     

Noncatalytic Biodiesel Fuel Production from Croton megalocarpus Oil

Biodiesel is currently considered as the most promising substitute for diesel fuel because of its similar properties to diesel. This study presents the use of the supercritical methanol method in the production of biodiesel from Croton megalocarpus oil. The reaction parameters such as methanol‐to‐oil ratio, reaction temperature and reaction time were varied to obtain the optimal reaction conditions by design of experiment, specifically, response surface methodology based on three‐variable central composite design with α = 2. It has been shown that it is possible to achieve methyl ester yields as high as 74.91 % with reaction conditions such as 50:1 methanol‐to‐oil molar ratio, 330 °C reaction temperature and a reaction period of 20 min. However, Croton‐based biodiesel did not sustain higher temperatures due to decomposition of polyunsaturated methyl linoleate, which is dominant in biodiesel. Lower yields were observed when higher temperatures were used during the optimization process. The supercritical methanol method showed competitive biodiesel yields when compared with catalytic methods.     

Wild Brazilian Mustard (Brassica juncea L.) Seed Oil Methyl Esters as Biodiesel Fuel

Wild mustard (Brassica juncea L.) oil is evaluated as a feedstock for biodiesel production. Biodiesel was obtained in 94 wt.% yield by a standard transesterification procedure with methanol and sodium methoxide catalyst. Wild mustard oil had a high content of erucic (13(Z)-docosenoic; 45.7 wt.%) acid, with linoleic (9(Z),12(Z)-octadecadienoic; 14.2 wt.%) and linolenic (9(Z),12(Z),15(Z)-octadecatrienoic; 13.0 wt.%) acids comprising most of the remaining fatty acid profile. The cetane number, kinematic viscosity, and oxidative stability (Rancimat method) of the methyl esters was 61.1, 5.33 mm² s⁻¹ (40 °C) and 4.8 h (110 °C), respectively. The cloud, pour and cold filter plugging points were 4, −21 and −3 °C, respectively. Other properties such as acid value, lubricity, free and total glycerol content, iodine value, Gardner color, specific gravity, as well as sulfur and phosphorous contents were also determined and are discussed in light of biodiesel standards ASTM D6751 and EN 14214. Also reported are the properties and composition of wild mustard oil, along with identification of wild mustard collected in Brazil as Brassica juncea L. (2n = 36) as opposed to the currently accepted Sinapis arvensis L. (2n = 18) classification. In summary, wild mustard oil appears to be an acceptable feedstock for biodiesel production. Disclaimer: Product names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also be suitable.     

Effect of Waste Cooking Oil Biodiesel on the Properties of Particulate from a DI Diesel Engine

The present work focuses on the effect of waste cooking oil biodiesel on the particulate mass, number concentration, nanostructure, and oxidative reactivity under different engine speeds and engine loads. Particulate samples were collected from the diluted exhaust of a medium-duty direct injection diesel engine and were used to analyze the physico-chemical properties via the transmission electron microscope (TEM) and the thermogravimetric analyzer/differential scanning calorimeter (TGA/DSC). The TEM images reveal that smaller primary particles are formed at higher engine speed, lower engine load, or using biodiesel. Quantitative analysis of the nanostructures indicates more soot with more disordered configuration, in which shorter and more curved graphene layer is prevailing at lower engine load or when using biodiesel. Furthermore, the TGA results infer that the soot oxidative reactivity is closely related to the nanostructure properties and the effect of engine load is more pronounced than the effect of engine speed. Also biodiesel soot has faster oxidative reactivity than diesel soot. Moreover, results obtained for B30 (30% biodiesel and 70% diesel fuel) lie in between those for biodiesel and diesel fuel.

Copyright 2015 American Association for Aerosol Research     

生物柴油及调和柴油低温流变性能研究

通过脂肪酸甲酯含量、冷滤点、倾点测定,对大豆油甲酯、花生油甲酯、棉籽油甲酯、棕榈油甲酯、棉籽油甲酯与花生油甲酯调和油、棕榈油甲酯与花生油甲酯以及生物油甲酯与石化柴油调和油的低温流动性能进行考察。脂肪酸甲酯冷滤点较高,两种脂肪酸甲酯按一定比例调和能改善其低温流动性。通过研究脂肪酸甲酯和脂肪酸甲酯调和油的粘温和流变性能,发现它们的表观粘度均随温度的降低而升高;在剪切率较高时表现为牛顿型流体,在剪切率较低时表现为剪切稀化的非牛顿型流体。剪切率和温度影响脂肪酸甲酯及其调和油的粘度,剪切率低、温度低时剪切稀化趋势明显。     

生物柴油和矿物柴油的性质对比

文章三种自制生物柴油性质完全符合德国现行生物柴油标准,基本符合0#矿物柴油标准。对比生物柴油与矿物柴油性质得出:生物柴油较矿物柴油更环保、更安全,但其低温性、蒸发性和雾化性不太理想,将其与矿物柴油调合使用,可以取长补短,发挥各自的优势。通过对调合油性质分析,结果表明,生物柴油和矿物柴油的适宜调合比为B20。     

Effects of NanoTag Markers in Palm Methyl Esters and Their Blends with Petroleum Diesel

Given the critical need to address smuggling and unauthorised usage of subsidised diesel, the Malaysia Government introduced fuel marking for subsidised diesel under the NanoTag Program in April 2006. NanoTag markers mixture consists of VisioTag (dye) and NanoTag (immunoassay marker) were spiked into palm methyl esters (PME) and its diesel blends. The blending ratio tested was 5, 10 and 20% (by volume) of fatty acid methyl esters (FAME) in diesel fuel. Both NanoTag and VisioTag markers were found to be stable in PME and blended fuel after 9 months of storage. The concentration of the NanoTag marker (MTK-021) remains consistent as determined by HPLC–UV detector. No colour change or discolouration was observed for the VisioTag marker. Other important fuel quality parameters such as acid value, oxidative stability, and moisture content of the samples were studied. The results showed that NanoTag markers pose no significant measurable effects on blended PME and diesel fuel quality upon storage up to B20.     

地沟油生物柴油流变学特性研究

生物柴油是一种可以替代矿物柴油使用的环保燃油和可再生能源,粘度是评价生物柴油流动性能的一个重要指标。文章对地沟油生物柴油和0#柴油混合的流变学特性进行研究,并确定了地沟油生物柴油的流体类型为牛顿流体,在剪切力作用下能保持很好的稳定性,其粘度不随搅拌时间的变化而变化,随浓度的增大而增加,温度的升高而降低。     

Methyl Esters (Biodiesel) from and Fatty Acid Profile of Gliricidia sepium Seed Oil

Increasing the supply of biodiesel by defining and developing additional feedstocks is important to overcome the still limited amounts available of this alternative fuel. In this connection, the methyl esters of the seed oil of Gliricidia sepium were synthesized and the significant fuel‐related properties were determined. The fatty acid profile was also determined with saturated fatty acids comprising slightly more than 35 %, 16.5 % palmitic, 14.5 % stearic, as well as lesser amounts of even longer‐chain fatty acids. Linoleic acid is the most prominent acid at about 49 %. Corresponding to the high content of saturated fatty acid methyl esters, cold flow is the most problematic property as shown by a high cloud point of slightly >20 °C. Otherwise, the properties of G. sepium methyl esters are acceptable for biodiesel use when comparing them to specifications in biodiesel standards but the problematic cold flow properties would need to be observed. The ¹H‐ and ¹³C‐NMR spectra of G. sepium methyl esters are reported.     

Effect of FFA of Crude Rice Bran Oil on the Properties of Diesel Blends

Crude rice bran oil (CRBO) with high free fatty acid (FFA) content is not suitable for eating purposes, however, it can be used as a fuel to partially replace or fully replace No.2 diesel. The main objective of the present work was to analyse the effect of FFA content of CRBO on the combustion properties such as viscosity, calorific value, volatility and aniline point. CRBO with different FFAs were collected and mixed with No.2 diesel to prepare CRBO-diesel blends. It was observed that the viscosity of the blends increased with increase in FFA while the calorific value decreased. Significant variations were observed in the distillation curve for the CRBO blends with different FFA. Aniline point of the blends was 10–15% lower than that of diesel and it is indirectly proportional to the FFA of CRBO in the blend. Experimental results showed that the combustion properties of CRBO are the function of the FFA in the oil. As a dilute blend with diesel, CRBO with high FFA content showed comparable combustion properties to that of diesel. The properties differed in magnitude by 10–15% when compared with diesel. From the present investigation it is concluded that in blended form, CRBO with high FFA can be a potential resource to utilize it as an alternative fuel for CI (compression ignition) engines.     

Effect of Palm Oil Enzymatic Interesterification on Physicochemical and Structural Properties of Mixed Fat Blends

The physicochemical properties of binary and ternary fat systems made of commercial samples of palm oil (PO) blended with anhydrous milk fat (AMF) and/or rapeseed oil (RO) were studied. Physical properties such as solid fat content by pulsed‐Nuclear Magnetic Resonance (p‐NMR), melting profile by differential scanning calorimetry (DSC), and polymorphism of the blends were investigated. Palm oil was then batch enzymatically interesterified for 27 h, using Lipozyme^® TL IM as biocatalyst, and further blended with AMF and/or RO in the same way. The objective of the present work was to evaluate the effect of batch enzymatic interesterification (B‐EIE) of palm oil on physical characteristics of the investigated fat blends. For that purpose, iso‐solid diagrams have been constructed from p‐NMR data. It was shown that B‐EIE of palm oil modifies its melting behaviour, but also its polymorphic stability and miscibility with other fats. Under dynamic conditions, after B‐EIE, the non‐ideal behaviour (eutectic) detected at low temperatures in the ternary PO/AMF/RO system disappears in the corresponding EIE‐PO/AMF/RO. After static crystallization followed by a tempering, the hardness of palm oil is increased after B‐EIE, as well as the hardnesses of the blends containing this fat compared to the native one. Polymorphism stability of the binary and ternary fat systems is also modified after B‐EIE compared to the corresponding native systems.     

Waste PU/PP Blends with Improved Technological Properties

An investigation is reported here which aims to study the possibility of recycling waste polyurethane powder by melt blending with polypropylene. Improvement in the technological properties is found to be possible by increasing the miscibility of the blend by using a series of maleic-anhydride based compatibilizers. Mechanical properties were found to increase with increase in the compatibilizer content. It is claimed that the explanations given in this paper are unique in that through the use of a series of maleic anhydride based compatibilizers with PU/PP blends, it is possible to get materials with high mechanical properties which is corroborated by morphological and contact angle studies.     

生物柴油掺烧甲醇对柴油机污染物影响研究

在186FA柴油机上,进行了燃用生物柴油和甲醇/生物柴油混合燃料的排放试验。研究结果表明,与燃用生物柴油相比,BM15在Pe=1.57 kW时CO升高279.1%,HC排放升高96.3%;随着混合燃料中甲醇浓度增加,NOx排放减少,标定转速满负荷BM15的NOx排放降低42.7%;低负荷时排气烟度相差不大,均不超过0.1 BSU,高负荷时BM15排气烟度降低51.2%。     

Glycerolysis of Crude Methyl Esters with Crude Glycerol from Biodiesel Production

Glycerolysis of crude fatty acid methyl esters (FAME) with crude glycerol derived from biodiesel production was performed. The reaction was accomplished at temperatures ranging between 160 and 200 °C and molar ratios of FAME to glycerol ranging between 1.5 and 3.0. Increasing the temperature improved the formation rate of monoglycerides (MG) and diglycerides (DG). However, increasing both the temperature and the molar ratio of glycerol to FAME diminished the formation of MG. Best results (43 % MG and 26 % DG in 10 min) were obtained at 200 °C using the lowest concentration of glycerol. The effects of soap and NaOH present in crude glycerol were controlled by carrying out the reaction with pure glycerol. In comparison with NaOH-catalyzed reactions, soap-catalyzed reactions resulted in a slower formation rate of products. However, soap-catalyzed reactions were less prone to secondary reactions, affording maximum yields of MG and DG, which were higher than those obtained with NaOH-catalyzed reactions at 180 and 200 °C.