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1.
A light commercial road vehicle fitted with a heated fuel line and tank was run on cold pressed and filtered camelina sativa seed oil and unheated mineral diesel fuel. It was found that the seed oil produced a maximum power at the road wheels of 43.25 kW and returned 12.57 km/l compared to 38.50 kW and 14.03 km/l for the mineral fuel. At an engine speed >2000 rpm and high loading, both smoke opacity and CO emitted from the exhaust was found to be approximately 50% lower with the seed oil than with the mineral fuel, however, NO was higher for the seed oil by almost 6% at engine speeds >3500 rpm, but similar <3500 rpm. The CO2 and O2 emissions were similar and NO2 emitted was negligible for both fuels. The effect of heating at 170 °C on the camelina sativa seed oil was investigated and a significant increase in viscosity was observed which coincided with a reduction in the iodine value of the oil.  相似文献   

2.
The feasibility of producing biodiesel from Idesia polycarpa var. vestita fruit oil was studied. A methyl ester biodiesel was prepared from refined I. polycarpa fruit oil using methanol and potassium hydroxide (KOH) in an alkali-catalyzed transesterification process. The experimental variables investigated in this study were catalyst concentration (0.5–2.0 wt.% of oil), methanol/oil molar ratio (4.5:1 to 6.5:1), temperature (20–60 °C) and reaction time (20–60 min). A maximum yield of over 99% of methyl esters in I. polycarpa fruit oil biodiesel was achieved using a 6:1 molar ratio of methanol to oil, 1.0% KOH (% oil) and reaction time for 40 min at 30 °C. The properties of I. polycarpa fruit oil methyl esters produced under optimum conditions were also analyzed for specifications for biodiesel as fuel in diesel engines according to China Biofuel Systems Standards. The fuel properties of the I. polycarpa fruit oil biodiesel obtained are similar to the No. 0 light diesel fuel and most of the parameters comply with the limits established by specifications for biodiesel.  相似文献   

3.
A genetically altered plant strain (Cuphea viscosissima VS-320) was identified which produces an oil with elevated levels of medium- and short-chain triglycerides. Previous studies have suggested that such an oil may be appropriate for use as a substitute for diesel fuel without chemical conversion of component triglycerides to methyl esters. This oil is also of interest for other industrial applications. This paper discusses the oil composition of C. viscosissima VS-320 and presents the analysis of several important alternative fuel screening properties of this oil: dynamic viscosity for shear rates of 1.617–64.69 s1 at temperatures of 25–80°C, boiling point at atmospheric pressure, temperature dependence of vapor pressure (from 40 to 760 mmHg for the 300–400°C temperature range), and heat of vaporization (ΔHv). These properties have been established as indicators of fuel performance and can be used for initial screening of possible diesel fuel substitutes. These properties are compared to those of diesel, biodiesel, and vegetable oils. Analysis of these properties suggests that further genetic development of this plant as a source of diesel fuel is warranted.  相似文献   

4.
With increased emphasis on bio-diesel fuels, the influence of spring planting on development of brown mustard (Brassica juncea cv. Arid), canola (B. napus cv. Hyola 401) and camelina (Camelina sativa cv. Boa) has become important. Field trials were conducted at Scottsbluff, NE, in 2005 and 2006 at planting dates of 24 February, 24 March, 7 April, 21 April and 5 May, and 3 March, 3 April, 10 April, 27 April, 11 May, and 2 Jun, respectively. Emergence time was shorter with later planting. Flowering date was later with later planting but occurred within a range of degree days (P-days). Fruiting was affected by date and P-days, but seed maturity was not affected by planting date and was unrelated to P-days. Fleabeetle (Phyllotreta spp.) damage was very high in brown mustard and canola. Bird, primarily house finch (Carppodacus mexicanus), feeding was a major problem with brown mustard planted before mid April and in canola, only with the first planting. Camelina was not affected by either. Planting in April gave the best yields, and canola could yield over 2200 kg ha−1. Oil content of the Brassica was highest when planted from late March and later. For camelina, planting date had no effect. In brown mustard and canola, 60-65% of oil was C18:1, in camelina, about 15%. Later planting increased C18:1 content for the three crops. The second fatty acid was C18:2 with 20% in brown mustard, 18% in canola and 20% in camelina. Later planting increased C18:2 in camelina only. The major fatty acid in camelina was C18:3 at 32-37%; earlier planting increased the content of C18:3. In Camelina, C20:1 comprised about 12% of the oil and was highest with April planting. Canola and camelina seeded in April could be grown for oil successfully in western Nebraska.  相似文献   

5.
选育高含油量双低油菜品种的理论与实践   总被引:27,自引:1,他引:27  
含油量作为油菜生产最终目标性状产油量的组成因素,与油菜生产效益的提高息息相关。在目前我国 油菜产量水平已得到相当程度提高的前提下,培育高含油量油菜品种是进一步发展油菜产业的必由之路。根据油 菜含油量的遗传特点,结合培育高含油量杂交油菜品种中油杂8号和中油杂11的体会,提出了除了利用黄籽以 外,培育大粒和适宜植株形态性状的品种也是提高油菜含油量的重要途径。初步构建了高含油量油菜品种的形态 组成,并基于近年来参加和通过国家区域试验的冬油菜品种含油量变化情况,展望了我国高含油量油菜育种的发 展前景。  相似文献   

6.
生物柴油物理特性参数的估算与误差分析   总被引:1,自引:0,他引:1  
以生物柴油脂肪酸酯含量为基础,应用Matlab编制了包含15种脂肪酸酯的生物柴油物性参数预测程序,并应用所编程序估算了大豆油甲酯生物柴油的密度、表面活力、黏度和导热系数;分析比较了各种估算方法的精度.结果表明:在生物柴油密度估算中,修改Raekett方程的估算精度较高;Sastfi-Rao方法估算生物柴油低温黏度所得结果与实测值最接近,其估算精度较高;Miller方法和Macleod-Sugden关联式估算生物柴油表面张力的精度较其它几种方法高;建议在生物柴油导热系数估算中应用Sastri方法.  相似文献   

7.
Present study was carried out in order to assess the constituents of Adenanthera pavonina wax esters by Fourier Transform Infrared (FT-IR) spectroscopy and Gas chromatography (GC). After extraction of oil from A. pavonina seeds, wax esters were separated from oil by centrifugation and then purified through crystallization process in acetone. The white crystalline solid with melting point of 83-85 °C was initially characterized as wax esters by FT-IR. Gas chromatography with flame ionization detector (GC-FID) provided the separation of various wax esters from C34 to C48 including odd and even chain esters. C46 wax ester was found to be predominant. For separation, identification and estimation of individual constituents of fatty acid methyl esters and fatty alcohol acetates were carried out by GC-MS after saponification and derivatization of wax esters. GC-MS analysis indicated the presence of saturated methyl esters from Cl4 to C30. Predominant methyl ester was C22. Wax esters contained the saturated fatty alcohols from C14 to C28. The major alcohol was saturated C24 fatty alcohol. The results indicated that A. pavonina wax esters have potential to be used in pharmaceutical and cosmetic industry due to its better composition of long chain fatty acids and fatty alcohols.  相似文献   

8.
Epoxidized methyl esters were prepared by the transesterification of epoxidized soybean oil (ESBO). The transesterification was complete in 10 min at 50 °C without loss of the epoxide function. Epoxidized methyl esters represent a renewable substrate that is readily converted into surfactants, fuel additives, and other industrial products. The implementation of this reaction will increase the availability of epoxidized methyl esters and promote the development of new biobased products.  相似文献   

9.
Palm esters were synthesized through enzymatic transesterification of various palm oil fractions with oleyl alcohol using Lipozyme RM IM as the catalyst. At the optimized alcoholysis reaction condition, after 5 h reaction time all palm oil fractions exhibited a high percentage yields of esters (>80%). Simultaneous differential scanning calorimeter-thermal gravity analysis showed a high thermal stability profile of palm esters. Other physicochemical properties of palm esters such as refractive index, density, surface tension, slip melting point, saponification value, iodine value and acid value were analyzed following standard test methods modified from the American Oil Chemists’ Society standards. The dermal irritation assay of palm oil esters shows the non-irritancy of the esters with a Human Irritancy Equivalent (HIE) score below 0.9. Furthermore, an increase in skin hydration of 40.7% after 90 min after application in an acute moisturizing test, has proven the suitably of palm oil esters to be used in the cosmetics formulation.  相似文献   

10.
Wide variability in oil content was observed in 75 germplasm accessions of Pongamia pinnata (L.) Pierre collected from Telengana region of Andhra Pradesh, India. Out of these, fatty acid profiles of 21 accessions with varying seed oil content were examined. Large variation was observed in stearic, oleic and linoleic fatty acid composition i.e. 1.83–11.50%, 46.66–65.35% and 12.02–32.58% respectively while less variation i.e. 9.25–12.87% was found with palmitic acid content. Saponification number (SN), iodine value (IV) and cetane number (CN) of fatty acid methyl esters of oils varied from 183.3 to 200.91, 74.78 to 100.98 and 50.85 to 59.11 respectively. Fatty acid composition, IV and CN were used to predict the quality of fatty acid methyl esters of oil for use as biodiesel. Fatty acid methyl esters of oils of P. pinnata accessions DORPP 49, 72 and 83 were found most suitable (CN more than 56.6) for use as biodiesel and they meet the major specification of biodiesel standards of USA, Germany and European Standard Organization. The range of variability found for various biodiesel standards in accessions of P. pinnata can be utilized for the establishment of plantations of promising genotypes through clonal means for increased productivity.  相似文献   

11.
This report presents a method for synthesizing base-stock for green industrial product from a vegetable oil with a high composition of unsaturated fatty acids. Epoxy methyl ester of palm kernel oil was synthesized from laboratory purified palm kernel oil using a two-step reaction and the products were used as a base-stock for green electrical insulation fluid. Epoxidized palm kernel oil was first prepared through epoxidation reaction involving purified palm kernel oil, acetic acid and hydrogen peroxide in the presence of amberlite as catalyst which lasted for 4 h. It was then followed by transesterification reaction involving the epoxidized product and methanol in the presence of sodium hydroxide as catalyst to synthesize the corresponding epoxy methyl ester. The thermal and electrical breakdown properties of the epoxy methyl ester demonstrated significantly improved properties for its use as raw material for bio-based industrial products such as electrical insulation fluids.  相似文献   

12.
This study investigates the development of thermoset plastics from plant-based oils (e.g., linseed, soybean, cottonseed, oilseed radish, and peanut oils) using an optimal process of solvent-free epoxidation. The epoxidation of plant oils can be accomplished economically by reacting the double bonds of fatty-acids with hydrogen peroxide. During the solvent-free process catalyzed by the ion-exchange resin, we observed that the influence of several variables was important: the molar ratio of hydrogen peroxide to unsaturation, acetic acid to unsaturation, and temperature. The epoxidation of plant oils was determined from the liquid mixture and the composite matrix by thermal and spectroscopic analyses. Compounds with a higher double-bond (iodine) value showed higher oxirane oxygen percent and selectivity, and a higher hydroxyl value because of a greater possibility of attack by solutions causing side reactions. Lower iodine values indicated fewer epoxy groups and selectivity, and a lower hydroxyl value. Benzyl pyrazinium hexafluoroantimonate (BPH) yielded good thermal curing properties; as little as 1% added to the plastics produced light-weight composites. Epoxidized linseed oil promises the highest modulus and impact resistance due to the largest number of double bonds to contribute more epoxy groups and the large proportion of linolenic acids to produce epoxy groups rapidly.  相似文献   

13.
Many research reported vegetable oil as a potential substitute for diesel engines with its ester form known as biodiesel. The biodiesel can be prepared by different process using vegetable oil and alcohol. The common process used for biodiesel preparation is known as transesterification. This paper presents the transesterification of Sal oil (Shorea robusta) into Sal oil methyl ester (SOME) and its performance in direct injection diesel engine. Several process parameters such as catalyst quantity, molar ratio of alcohol, reaction temperature and reaction time were studied and the optimized process conditions are amount of catalyst (NaOH) - 0.25 wt%, alcohol (methanol) - 150% excess, reaction temperature - 65 °C and reaction time - 1.5 h. The studies with SOME as fuel in the direct injection diesel engine shows that the exhaust emissions such as CO, HC and NOx are reduced by 25%, 45% and 12%, respectively compared to diesel without significant difference in thermal efficiency. Based on this study it is concluded that the SOME can be used as fuel without any modifications in the engine and hence this biodiesel can be a potential substitute to standard diesel fuel.  相似文献   

14.
A new series of petroselinic (Coriandrum sativum L.) based estolide 2-ethylhexyl (2-EH) esters were synthesized, as the capping material varied in length and in degrees of unsaturation, in a perchloric acid catalyzed one-pot process with the esterification process incorporated into an in situ second step to provide the coriander estolide 2-EH ester. The kinematic viscosities ranged from 53 to 75 cSt at 40 °C and 9.1 to 14.6 cSt at 100 °C with a viscosity index (VI) ranging from 151 to 165. The caprylic (C8) capped coriander estolide 2-EH ester had the lowest low-temperature properties (pour point = −33 °C and cloud point = −33 °C), while the coco-coriander estolide 2-EH ester produced an estolide with modest low-temperature properties (pour point = −24 °C and cloud point = −25 °C). The coco-coriander estolide 2-EH ester was explored for the ability to resist oxidative degradation with the use of an biodegradable additive package added in 1.5%, 3.5%, or 7.0% units based on weight. The oxidative stability increased as the amount of stability package increased (rotating pressurized vessel oxidation test (RPVOT) times 65-273 min). Along with expected good biodegradability, these coriander estolide 2-EH esters had acceptable properties that should provide a specialty niche in the U.S. as a biobased lubricant.  相似文献   

15.
Saturated mono-estolide methyl esters and enriched saturated mono-estolide 2-EH esters were synthesized from oleic and different saturated fatty acids under three different synthetic routes. Estolide numbers (EN), the average number of fatty acid units added to a base fatty acid, varied with synthetic conditions. The attempts at obtaining saturated mono-estolide 2-EH esters, EN = 1, via distillation proved to be challenging, which lead to estolide samples with EN > 1 and the pour point values followed the same trend as the high EN estolides. The other synthetic routes provided saturated mono-estolide methyl esters with EN = 1. The resulting pour point values showed a linear relationship between the saturated capping chain length and pour point. As the saturated capping chain length increased the pour points also increased (higher temperatures): C-2 capped ?30 °C, C-10 capped ?12 °C, and C-18 capped 3 °C.The saturated mono-estolide methyl ester viscosities also showed an increase in viscosity at 40 and 100 °C as the saturated chain lengths increased. The viscosities for the C-4 saturated mono-estolide methyl ester was 9.5 cSt at 40 °C and 2.6 cSt at 100 °C, while medium chain length derivations (C-10 saturated mono-estolide methyl ester) were 19.7 cSt at 40 °C and 4.2 cSt at 100 °C, and at the longer chain length derivations (C-18 mono-estolide methyl esters) were 27.6 cSt at 40 °C and 10.7 cSt at 100 °C. In general, a new series of saturated oleic mono-estolide methyl esters were synthesized and physical properties were collected. The physical property data indicated that both chain length and EN affect low temperature properties.  相似文献   

16.
一种高利用价值油料作物—亚麻荠的研究进展   总被引:2,自引:0,他引:2  
本文在对亚麻荠的栽培和育种现状进行阐述的基础上,重点概括了其种子中两种主要化学成分油脂和蛋白,具体包括油脂含量和脂肪酸组成、脂质活性成分及降血脂作用、油脂在生物能源上的应用,蛋白含量和氨基酸组成、蛋白饼粕加工利用等方面的研究状况。最后分析了约束亚麻荠发展的因素,并提出了相应的建议。  相似文献   

17.
Camelina (Camelina sativa L.) was introduced for the first time in Chile in 2008 as a potential feedstock for biodiesel and also as high omega-3-containing seed oil for the salmon feed industry. The objective of this study was to determine the optimum seeding date to maximize camelina seed yield in South Central Chile. The experiment was conducted under dryland conditions in Chillán, El Carmen, Los Angeles, Gorbea, and Osorno in 2008 and in Chillán and Los Angeles in 2009. The experimental design was a RCB with a split-plot arrangement with four replicates, where the main plot was the seeding date (five dates) and the sub-plot the spring type cultivars (Gold of Pleasure, Suneson, and Blaine Creek). Seeding dates at each environment were targeted to 30 April, 15 May, 30 May, 30 June, and 30 July of 2008 and 2009. The combined analysis of variance indicated no cultivar main effect or interactions with cultivar. The date by environment interaction was significant for seed yield. There were no seed yield differences among seeding dates in Chillán and El Carmen. The first three seeding dates were the highest yielding in Los Angeles and Osorno, and only the first seeding date was significantly higher in seed yield in Gorbea. Highest seed yield at Los Angeles, Gorbea, and Osorno were 1995, 1310, and 2314 kg ha−1. Seed oil content was not different among seeding dates in Chillán and El Carmen. Highest seed oil content occurred at Osorno and Gorbea on the first three seeding dates and ranged from 420 to 457 g kg−1. Spring camelina cultivars are well adapted to South Central Chile as a winter annual crop when seeded before 15 May except in Osorno when seeded before 30 May. No disease or insectpests were observed except for Aster Yellow infestation at Chillán and Los Angeles. Camelina has great potential as an oilseed for biodiesel and as a source of omega-3 for the pharmaceutical industry but markets for it need to be developed locally for camelina to become an option for growers.  相似文献   

18.
By activating corn starch with acetic acid and using acetic anhydride as an esterifying agent, starch acetates with increasing degrees of substitution were obtained using microwave assistance when the amount of iodine varied from 0.5 to 1.75 mmol. The study of Fourier Transform Infrared (FT-IR) spectra, X-ray diffraction pattern, thermal properties, granule morphology, water absorption and solubility, revealed important changes on the physical properties of the obtained products related to the increase of the iodine content. As shown by the scanning electron microscope (SEM), a specific structure on the granule surface was discerned for each amount of iodine. By its exo-corrosive action on starch, iodine indirectly induced loss of crystallinity, decrease of the glass transition and melting temperatures, and a progressive reduction in the water absorption and water solubility index of the modified products. Starch esters with better hydrophobicity and good processability for bio-based material applications were synthesized. Alternatively, the variation in the concentration of the iodine could also be of interest in special purposes, in which starch granules with controlled surface porosity are needed.  相似文献   

19.
The high viscosity of vegetable oil can be reduced by transesterification with alcohols and converting it into biodiesel. Biodiesel can be used neat or blended with diesel as engine fuel. This study demonstrates that esters of castor oils have a higher viscosity than safflower oil derived esters and the viscosity can be reduced by blending with diesel. The viscosity increased in a non-linear fashion as the percentage of castor esters increased in castor esters diesel blends and in castor esters safflower esters blends. Only slight increases in viscosity were observed for B40 and B60 mixtures with No. 2 diesel. Addition of ten chemical additives in castor esters at the rate of 0.01%, 0.1% and 1.0% showed limited viscosity reduction.  相似文献   

20.
The oxidative stability indices (OSI) of several vegetable oils were determined at 110°C. Meadowfoam oil, Limnanthes alba, was found to be the most stable oil with an OSI time of 67.3 h for refined oil and 246.9 h for crude oil. Other oils with good oxidative stabilities were refined high oleic sunflower and crude jojoba oil (Simmondsia chinensis) with OSI times of 49.8 and 34.5 h respectively. The unusually high OSI time of crude meadowfoam oil could not be attributed to its tocopherol content since refining did not significantly alter the tocopherol content, but significantly reduced the stability. A relationship of iodine value to antioxidant was developed for vegetable oils; however, this linear relationship did not account for the unusually high oxidative stability of meadowfoam oil. Binary mixtures of vegetable oils were also examined for enhanced oxidative stability. Small amounts of crude meadowfoam oil gave enhanced oxidative stability in mixtures with jojoba, triolein and castor oils. Triolein/crude meadowfoam oil mixtures showed the most dramatic improvements in OSI time with a 5% (w/w) addition of crude meadowfoam causing a 21-fold increase in the OSI time. Meadowfoam mixtures with jojoba improved the OSI time of jojoba from 31.1 to 52.7 h, when 10% crude meadowfoam oil was added. A study of oxidative stability with respect to olefin position showed that the Δ5 double bond was the most stable by more than an order of magnitude. The oxidative stability of meadowfoam FAMEs at 90°C gave an OSI time of 4.9 h which was the same as methyl erucate and methyl petroselenate, but less than methyl oleate which had an OSI time of 14.8 h. However, when methyl 5-eicosenoate was isolated in high purity (monoene >96%) and tested, it gave an OSI time of 69.4 h.  相似文献   

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