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1.
Improving the low-temperature properties of alternative diesel fuels: Vegetable oil-derived methyl esters 总被引:14,自引:0,他引:14
R. O. Dunn M. W. Shockley M. O. Bagby 《Journal of the American Oil Chemists' Society》1996,73(12):1719-1728
This work explores near-term approaches for improving the low-temperature properties of triglyceride oil-derived fuels for
direct-injection compression-ignition (diesel) engines. Methyl esters from transesterified soybean oil were evaluated as a
neat fuel and in blends with petroleum middle distillates. Winterization showed that the cloud point (CP) of methyl soyate
may be reduced to −16°C. Twelve cold-flow additives marketed for distillates were tested by standard petroleum methodologies,
including CP, pour point (PP), kinematic viscosity, cold filter plugging point (CFPP), and low-temperature flow test (LTFT).
Results showed that additive treatment significantly improves the PP of distillate/methyl ester blends; however, additives
do not greatly affect CP or viscosity. Both CFPP and LTFT were nearly linear functions of CP, a result that compares well
with earlier studies with untreated distillate/methyl ester blends. In particular, additives proved capable of reducing LTFT
of neart methyl esters by 5–6°C. This work supports earlier research on the low-temperature properties; that is, approaches
for improving the cold flow of methyl ester-based diesel fuels should continue to focus on reducing CP. 相似文献
2.
This work examines low-temperature properties of triglyceride-based alternate fuels for direct-injection compression-ignition
engines. Methyl esters from transesterified soybean oil were studied as neat fuels and in blends with petroleum middle distillates
(No. 1 or No. 2 diesel fuel). Admixed methyl esters composed of 5–30 vol% tallowate methyl esters in soyate methyl esters
were also examined. Pour points, cloud points, and kinematic viscosities were measured; viscosities at cooler temperatures
were studied to evaluate effects of sustained exposure. Low-temperature filterability studies were conducted in accordance
with two standard methodologies. The North American standard was the low-temperature flow test (LTFT), and its European equivalent
was the cold-filter plugging point (CFPP). With respect to cold-flow properties, blending methyl esters with middle distillates
is limited to relatively low ester contents before the properties become preclusive. Under most conditions, cold-flow properties
were not greatly affected by admixing the methyl esters with up to 30 vol% tallowate (before blending). Least squares analysis
showed that both LTFT and CFPP of formulations containing at least 10 vol% methyl esters are linear functions of cloud point.
In addition, statistical analysis of the LTFT data showed a strong 1:1 correlation between LTFT and CP. This result may prove
crucial in efforts to improve low-temperature flow properties of alternate diesel fuels that contain methyl esters derived
from triglycerides. 相似文献
3.
Robert O. Dunn Victor T. Wyatt Karen Wagner Helen Ngo Megan E. Hums 《Journal of the American Oil Chemists' Society》2019,96(7):805-823
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 (TL) = CP + 5 °C (νL). Although the BCAE additives were more effective than SME, relatively large additive concentrations (yAdd) 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 yAdd = 0.50, 2EH-iOL should not exceed yAdd = 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 yAdd for SGME/BCAE admixtures were speculated to have been affected by the low-temperature rheology of SGME. 相似文献
4.
R. O. Dunn 《Journal of the American Oil Chemists' Society》2002,79(7):709-715
Vegetable oils are an attractive renewable source for alternative diesel fuels. However, the relatively high kinematic viscosity
of vegetable oils must be reduced to make them more compatible with conventional compression-ignition engines and fuel systems.
Cosolvent blending is a low-cost and easy-to-adapt technology that reduces viscosity by diluting the vegetable oil with a
low-M.W. alcohol (methanol or ethanol). The cosolvent (A), which consists of one or more amphiphilic compounds, is added to solubilize the otherwise nearly immiscible oil-polar alcohol
mixture. This work investigates cold flow properties and phase equilibrium behavior associated with blends consisting of soybean
oil (SBO) and methanol where A=8∶1 (mol) n-butanol/oleyl alcohol; 6∶1 (mol) 2-octanol/triethylammonium linoleate; and 4∶1 (mol) 2-octanol/Unadol 40 (alcohols from SBO
FA); and a blend of 2∶1 (vol/vol) No. 2 diesel fuel/SBO and 95% ethanol where A=n-butanol. Cloud point (CP), pour point, cold filter plugging point (CFPP), and low-temperature flow test (LTFT) results were
compared with corresponding phase separation temperature (T
ϕ) data measured at equilibrium. Although CP data were measured under non-equilibrium experimental conditions, a nearly linear
correlation was found between T
ϕ and CP. Statistical analysis showed that T
ϕ may also be correlated with CFPP and LTFT. Analysis of heating and cooling DSC curves indicated that peak temperatures may
be employed to predict cold flow properties and T
ϕ behavior for SBO/cosolvent blends. Cooling curve parameters correlated more readily than heating curve parameters. Finally,
relatively low quantities of heat evolved during freezing indicated that crystallization in the SBO/cosolvent blends studied
in this work occurs easily during cooling. 相似文献
5.
Robert O. Dunn Helen L. Ngo Michael J. Haas 《Journal of the American Oil Chemists' Society》2015,92(6):853-869
Biodiesel is an alternative diesel fuel derived mainly from the transesterification of plant oils with methanol or ethanol. This fuel is generally made from commodity oils such as canola, palm or soybean and has a number of properties that make it compatible in compression‐ignition engines. Despite its many advantages, biodiesel has poor cold flow properties that may impact its deployment during cooler months in moderate temperature climates. This work is a study on the use of skeletally branched‐chain‐fatty acid methyl esters (BC‐FAME) as additives and diluents to decrease the cloud point (CP) and pour point (PP) of biodiesel. Two BC‐FAME, methyl iso‐oleate and methyl iso‐stearate isomers (Me iso‐C18:1 and Me iso‐C18:0), were tested in mixtures with fatty acid methyl esters (FAME) of canola, palm and soybean oil (CaME, PME and SME). Results showed that mixing linear FAME with up to 2 mass% BC‐FAME did not greatly affect CP, PP or kinematic viscosity (ν) relative to the unmixed biodiesel fuels. In contrast, higher concentrations of BC‐FAME, namely between 17 and 39 mass%, significantly improved CP and PP without raising ν in excess of limits in the biodiesel fuel standard specification ASTM D 6751. Furthermore, it is shown that biodiesel/Me iso‐C18:0 mixtures matched or exceeded the performance of biodiesel/Me iso‐C18:1 mixtures in terms of decreasing CP and PP under certain conditions. This was taken as evidence that additives or diluents with chemical structures based on long‐chain saturated chains may be more effective at reducing the cold flow properties of mixtures with biodiesel than structures based on long‐chain unsaturated chains. 相似文献
6.
Robert O. Dunn 《Journal of the American Oil Chemists' Society》2012,89(8):1509-1520
Biodiesel is a renewable alternative fuel made from plant oils and animal fats that may be burned in a compression–ignition (diesel) engine. It is composed of mono-alkyl fatty acid esters made from plant oils or animal fats mainly by transesterification with methanol or ethanol. This process leaves behind small concentrations of minor constituents including monoacylglycerols (MAG). Saturated MAG have low solubility in biodiesel and may form solid residues during storage in cold weather. Soybean oil-fatty acid methyl esters (SME) were mixed with up to 1.0 mass% MAG to evaluate the effects on cloud point (CP), freezing point (FP), cold filter plugging point (CFPP), and wax appearance point (WAP). Differential scanning calorimetry (DSC) results showed that MAG with only 27.6 mass% total long chain (C16–C18) saturated fatty acid content had melting transitions between 54 and 59.0 °C. Furthermore, DSC analysis indicated that pure monoolein may be problematic with respect to melting transitions between 25.4 and 33.4 °C. Solubility data for SME–MAG mixtures indicated a broad transition temperature range from solid at low temperature to liquid at temperatures exceeding 60 °C. Increasing the added MAG content from 0.10 to 1.0 mass% increased both CP and FP. Cold filter plugging point demonstrated higher sensitivity than CP or FP at added MAG content below 0.10 mass%, though it was not affected by increasing MAG concentration above 0.50 mass%. Wax appearance point showed no effects until added MAG content exceeded 0.25 mass%. Kinematic viscosity measured at 5 °C similarly showed no effects until added MAG concentration exceeded 0.20 mass%. Specific gravity at 15.6 °C and refractive index at 25 °C were not greatly affected by added MAG except at concentrations greater than 0.10 mass%. 相似文献
7.
Baoting Su Lulu Wang Yuan Xue Jincan Yan Zhenbiao Dong Hualin Lin Sheng Han 《Journal of the American Oil Chemists' Society》2021,98(2):163-172
Poor cold flow property is a major issue that hinders the application of biodiesel-diesel blends. In this work, a series of methacrylate-benzyl methacrylate-N-vinyl-2-pyrrolidone terpolymers (RMC-MB-NVP, R = C12, C14, C16, C18) was synthesized and used as the pour point depressants (PPD) for waste cooking oil biodiesel blends. To further improve their depressive effects, dispersants, including Tween (40, 60, and 80), Span (40, 60, and 80), phthalic acid esters (PAE), and fatty alcohol polyoxyethylene ether (FAPE; FAPE 5, FAPE 7, and FAPE 9), were optimized and combined with the C14MC-MB-NVP terpolymers. The effects of C14MC-MB-NVP terpolymers and combined PPD (PPDC) on the cloud point (CP), cold filter-plugging point (CFPP), and pour point (PP) of biodiesel blends were studied. Here, results showed that the presence of dispersants can efficiently enhance the solubility and dispersibility of polymeric PPD in biodiesel blends; thus, the PPDC presents better depressive effects. Among them, C16MC-MB-NVP (5:1:1) combined with FAPE 7 dispersant at 4:1 mass ratio (PPDC-FAPE 7) showed the best synergistic effect, and the CP, CFPP, and PP of B20 treated with 2000 ppm PPDC-FAPE 7 decreased by 4, 10, and 19 °C, respectively. Moreover, differential scanning calorimetry, polarizing optical microscope, and rheological analyses were performed to rationalize the action mechanism of these PPD and dispersants in biodiesel blends. 相似文献
8.
Use of branched-chain esters to reduce the crystallization temperature of biodiesel 总被引:12,自引:17,他引:12
Inmok Lee Lawrence A. Johnson Earl G. Hammond 《Journal of the American Oil Chemists' Society》1995,72(10):1155-1160
To reduce the tendency of biodiesel to crystallize at low temperatures, branched-chain alcohols were used to esterify various
fats and oils, and the crystallization properties of the branched esters were compared with those of methyl esters by using
differential scanning calorimetry (DSC), cloud point, and pour point. Compared with the methyl esters that are commonly used
in biodiesel, branched-chain esters greatly reduced the crystallization onset temperature (TCO) of neat esters and their corresponding ester diesel fuel blends. Isopropyl and 2-butyl esters of normal (∼10 wt% palmitate)
soybean oil (SBO) crystallized 7–11 and 12–14°C lower, respectively, than the corresponding methyl esters. The benefit of
the branched-chain esters in lowering TCO increased when the esters were blended with diesel fuel. Esters made from a low-palmitate (3.8%) SBO crystallized 5–6°C lower
than those of normal SBO. Isopropyl esters of lard and tallow had TCO values similar to that of methyl esters of SBO. DSC provided an accurate means of monitoring crystallization, and the DSC
results correlated with cloud and pour point measurements. 相似文献
9.
A Comprehensive Evaluation of the Melting Points of Fatty Acids and Esters Determined by Differential Scanning Calorimetry 总被引:1,自引:0,他引:1
The melting point is one of the most important physical properties of a chemical compound and it plays a significant role
in determining possible applications. For fatty acid esters the melting point is essential for a variety of food and non-food
applications, the latter including biodiesel and its cold-flow properties. In this work, the melting points of fatty acids
and esters (methyl, ethyl, propyl, butyl) in the C8–C24 range were determined by differential scanning calorimetry (DSC), many of which for the first time. Data for triacylglycerols
as well as ricinoleic acid and its methyl and ethyl esters were also acquired. For some compounds whose melting points have
been previously reported, data discrepancies exist and a comprehensive determination by DSC has not been available. Variations
in the present data up to several °C compared to data in prior literature were observed. The melting points of some methyl-branched
iso- and anteiso-acids and esters were also determined. Previously unreported systematic effects of compound structure on
melting point are presented, including those for ω-9 monounsaturated fatty acids and esters as well as for methyl-branched
iso and anteiso fatty acids and esters. The melting point of a pure fatty acid or ester as determined by DSC can vary up to
approximately 1 °C. Other thermal data, including heat flow and melting onset temperatures are briefly discussed.
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. 相似文献
10.
Crystallization Behavior of Fatty Acid Methyl Esters 总被引:3,自引:1,他引:2
Robert O. Dunn 《Journal of the American Oil Chemists' Society》2008,85(10):961-972
Biodiesel from most agricultural feedstocks has flow properties that are prone to startup and operability problems during
cold weather. Biodiesel from soybean oil is generally a mixture of long-chain fatty acid alkyl esters composed of 0.15–0.20
mass fraction saturated esters (melting point [MP] ≫ 0 °C) mixed with unsaturated esters (MP < 0 °C). This work investigates
the crystallization properties of two saturated fatty acid methyl esters (FAME) commonly found in biodiesel from soybean oil.
Differential scanning calorimetry (DSC) heating and cooling scans of methyl palmitate (MeC16), methyl stearate (MeC18) and
methyl oleate (MeC18:1) in pure form were analyzed. Crystallization behavior in ternary FAME mixtures was inferred by the
application of thermodynamic models based on ideal solution and freezing-point depression theories. Activity coefficients
for MeC16 and MeC18 in MeC18:1 solvent were determined by analyzing DSC cooling curves for binary FAME mixtures. Eutectic
points were predicted by both models. Crystallization onset temperatures inferred from freezing point depression theory were
more accurate than those for ideal solutions with respect to a direct DSC cooling curve analysis of corresponding ternary
mixtures. This work shows that the crystallization onset temperature (cloud point) of biodiesel may be predicted by freezing-point
depression theory if the activity coefficients of the component FAME are known.
The use of trade, firm, or corporation names in this publication is for the information and convenience of the reader. Such
use does not constitute an official endorsement or approval by USDA or ARS of any product or service to the exclusion of others
that may be suitable. 相似文献
11.
Hem Joshi Bryan R. Moser Shailesh N. Shah Anurag Mandalika Terry Walker 《European Journal of Lipid Science and Technology》2010,112(7):802-809
The low temperature operability and oxidative stability of cottonseed oil methyl esters (CSME) were improved with four anti‐gel additives as well as one antioxidant additive, gossypol. Low temperature operability and oxidative stability of CSME was determined by cloud point (CP), pour point (PP), cold filter plugging point (CFPP), and oxidative stability index (OSI). The most significant reductions in CP, PP, and CFPP in all cases were obtained with Technol®, with the average reduction in temperature found to be 3.9 °C. Gunk®, Heet®, and Howe's® were progressively less effective, as indicated by average reductions in temperature of 3.4, 3.0, and 2.8 °C, respectively. In all cases, the magnitude of CFPP reduction was greater than for PP and especially CP. Addition of gossypol, a polyphenolic aldehyde, resulted in linear improvement in OSI (R2 = 0.9804). The OSI of CSME increased from 5.0 to 8.3 h with gossypol at a concentration of 1000 ppm. 相似文献
12.
Tocopherols were found to be the principal natural antioxidants in biodiesel grade fatty acid methyl esters. The stabilising
effect of α-, γ- and δ- tocopherols from 250 to 2,000 mg/kg was evaluated by thermal and accelerated storage induction times
based on rapid viscosity increase, in sunflower (SME), recycled vegetable oil (RVOME), rapeseed (RME) and tallow (TME) methyl
esters. Both induction times showed that stabilising effect is of the order of δ- > γ- > α-tocopherol, and that the stabilising
effect increased with concentration. The correlation between the two induction times however was poor, which is probably due
to the fact that the time they correspond to two different stages of oxidation. Tocopherols were found to stabilise methyl
esters by reducing the rate of peroxide formation while present. The deactivation rates of tocopherols increased with unsaturation
of the particular methyl ester and in the present work they were of the order of SME > RME > RVOME > TME. While α-tocopherol
was found to be a relatively weak antioxidants, both γ- and δ- tocopherols increased induction times significantly and should
be added to methyl esters without natural antioxidants. 相似文献
13.
Ramasubramania Iyer 《Journal of the American Oil Chemists' Society》2013,90(10):1569-1576
Cloud points (CPs) of five vegetable oil fatty acid methyl esters (FAME) and three biodiesel mixtures estimated by a thermodynamic equation were compared to measured CPs. The results indicate that estimated CP of peanut oil FAME are similar to measured CP and for three biodiesel mixtures a minimum total saturated FAME (SFAME) concentration is required for measured CPs to be closer to estimated CPs. These comparisons provide the basis for comments on using this method for estimating CPs of 22 test data of microalgae FAME. Cold filter plugging points (CFPPs) calculated by equation CFPP = 1.0191 × CP ? 2.9 with CPs verified from the thermodynamic equation was found to be identical to CFPPs reported in literature for 22 test data of microalgae FAME. Therefore these CPs were inserted in equation CFPP = CP ?4.5 for another set of CFPPs. Plots of CFPPs versus percent SFAME of the 22 test data of microalgae FAME (>12 %) for these two equations indicates that CFPP is controlled by 85 % of SFAME. Calculated CFPPs of vegetable oil FAME and biodiesel mixtures using both equations for estimated and measured CPs is discussed. Low concentrations of long chain saturated FAME impacting the estimation of CPs of vegetable oil FAME is used as a rationale to discuss the role of unidentified other species (OS) in estimation of CPs of microalgae FAME. 相似文献
14.
Fuel properties and nitrogen oxide emission levels of biodiesel produced from animal fats 总被引:2,自引:0,他引:2
FAME of lard, beef tallow, and chicken fat were prepared by base-catalyzed transesterification for use as biodiesel fuels.
Selected fuel properties of the neat fat-derived methyl esters (B100) were determined and found to meet ASTM specifications.
The cold-flow properties, lubricity, and oxidative stability of the B100 fat-derived fuels also were measured. In general,
the cold-flow properties of the fat-based fuels were less desirable than those of soy-based biodiesel, but the lubricity and
oxidative stability of the fat-based biodiesels were comparable to or better than soy-based biodiesel. Nitrogen oxide (NOx) emission tests also were conducted with the animal fat-derived esters and compared with soybean oil biodiesel as 20 vol%
blends (B20) in petroleum diesel. The data indicated that the three animal fat-based B20 fuels had lower NOx emission levels (3.2–6.2%) than did the soy-based B20 fuel. 相似文献
15.
Yuan Xue Lihong Wang Hualin Lin Sheng Han Shiyou Zheng 《Journal of the American Oil Chemists' Society》2021,98(9):943-954
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. 相似文献
16.
Robert O. Dunn 《Journal of the American Oil Chemists' Society》2013,90(12):1883-1894
Biodiesel is an alternative fuel composed of mono‐alkyl fatty acid esters made from the transesterification of plant oils or animal fats with methanol or ethanol. After conversion, biodiesel may contain trace concentrations of unconverted monoacylglycerols (MAG). These MAG have low solubility in biodiesel and may form solid residues when stored at cold temperatures. The present study evaluates the measurement of kinematic viscosity (ν) and cold filter plugging point (CFPP)‐time to filter (Δt) as parameters that predict the temperature where small concentrations of MAG may lead to formation of solids or other phase transitions that restrict the flow of soybean oil fatty acid methyl esters (SME) through filters and fuel lines. Mixtures of SME doped with MAG were prepared and ν and Δt were measured as the temperature decreased from 20 to below 0 °C. Results showed a correlation between ν and Δt that held for neat SME (SME without added MAG) and SME‐MAG mixtures as the temperature decreased to the threshold temperature (Tth). Sharp increases in Δt disrupted the correlation as temperature decreased below Tth. Furthermore, Tth generally increased as added MAG concentration increased in the mixtures. 相似文献
17.
Latifa Seniorita Eiji Minami Yoshiteru Yazawa Hitoshi Hayashi Shiro Saka 《Journal of the American Oil Chemists' Society》2019,96(9):979-987
Monoacylglycerols (MAG) are impurities present in biodiesel as a result of incomplete reactions. MAG often solidify in biodiesel even at room temperature because of their high melting points. This worsens the cold-flow properties such as the cloud point and pour point. We hypothesized that several types of MAG solidify simultaneously; therefore, we performed differential scanning calorimetry of binary mixtures of MAG to elucidate their interactions during solidification. Three thermodynamic formulas were then applied to the experimental results: (1) non-solid-solution, (2) solid-solution, and (3) compound formation models. Binary mixtures of MAG showed complicated liquidus curves with multiple upward convex shapes, with which only the compound formation model fitted well. This model was applied to multicomponent mixtures that consisted of MAG and fatty acid methyl esters (FAME) as surrogate biodiesel fuels. We confirmed that the model still worked well. The results show that the compound formation model has good potential for predicting the cold-flow properties of biodiesel. 相似文献
18.
Biodiesel is an alternative fuel for diesel engines that consists of the monoalkyl esters of vegetable oils or animal fats.
Currently, most biodiesel consists of methyl esters, which have poor cold-flow properties. Methyl esters of soybean oil will
crystallize and plug fuel filters and lines at about 0°C. However, isopropyl esters have better cold-flow properties than
methyl esters. This paper describes the production of isopropyl esters and their evaluation in a diesel engine. The effects
of the alcohol amount, the catalyst amount, and two different catalysts on producing quality biodiesel were studied. Both
sodium isopropoxide and potassium isopropoxide were found to be suitable for use in the transesterification process. A 20∶1
alcohol/TG molar ratio and a catalyst amount equal to 1% by weight (based on the TG amount) of sodium metal was the most cost-effective
way to produce biodiesel fuel. The emissions from a diesel engine running on isopropyl esters made from soybean oil and yellow
grease were investigated by comparing them with No. 2 diesel fuel and methyl esters. For nitrogen oxide emission, the difference
between the biodiesel produced from soybean oil and yellow grease was greater than the difference between the methyl and isopropyl
esters of both feedstocks. The other emissions from using isopropyl esters were about 50% lower in hydrocarbons, 10–20% lower
in carbon monoxide, and 40% lower in smoke number when compared with No. 2 diesel fuel. 相似文献
19.
Kiril Kazancev Violeta Makareviciene Valdas Paulauskas Prutenis Janulis 《European Journal of Lipid Science and Technology》2006,108(9):753-758
The aims of the present study were to evaluate the cold temperature behavior of methyl esters of vegetable and animal origin and of their mixtures with fossil diesel fuel, as well as to investigate the effectiveness of different depressants. Various blends of rapeseed oil methyl esters, linseed oil methyl esters, pork lard methyl esters and fossil diesel fuel were prepared, and both cloud point and cold filter plugging point (CFPP) were analyzed. It was found that mixtures with CFPP values of –5 °C and lower may contain up to 25% of pork lard methyl esters; whereas the ratio of summer fossil diesel fuel and rapeseed oil methyl esters may vary over a wide range, i.e. such mixtures can be used in a diesel engine in the summer. In the transitory periods it is possible to use up to 20% animal and vegetable ester blends (3 : 7) with winter fossil diesel, whereas only up to 5% of esters can be added to the fuel used in winter. In order to improve the cold properties of rapeseed oil, pork lard and linseed oil methyl ester mixtures, various additives were tested. Depressant Viscoplex 10–35 with an optimal dose of 5000 mg/kg was found to be the most effective. 相似文献
20.
EsMOVS柴油降凝剂的研制 总被引:9,自引:0,他引:9
对柴油降凝剂EsMOVS的合成、用途、使用条件、影响因素等作了阐述。此降凝剂对抚顺石油二厂-10#柴油的纯降凝度是18℃,冷滤点纯降低度是9℃。对其它柴油也有一定的降凝助滤效果。 相似文献