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1.
Ethyl acetate was explored as an acyl acceptor for immobilized lipase-catalyzed preparation of biodiesel from the crude oils of Jatropha curcas (jatropha), Pongamia pinnata (karanj) and Helianthus annuus (sunflower). The optimum reaction conditions for interesterification of the oils with ethyl acetate were 10% of Novozym-435 (immobilized Candida antarctica lipase B) based on oil weight, ethyl acetate to oil molar ratio of 11:1 and the reaction period of 12h at 50 degrees C. The maximum yield of ethyl esters was 91.3%, 90% and 92.7% with crude jatropha, karanj and sunflower oils, respectively under the above optimum conditions. Reusability of the lipase over repeated cycles in interesterification and ethanolysis was also investigated under standard reaction conditions. The relative activity of lipase could be well maintained over twelve repeated cycles with ethyl acetate while it reached to zero by 6th cycle when ethanol was used as an acyl acceptor.  相似文献   

2.
Propan-2-ol was used as an acyl acceptor for immobilized lipase-catalyzed preparation of biodiesel. The optimum conditions for transesterification of crude jatropha (Jatropha curcas), karanj (Pongamia pinnata) and sunflower (Helianthus annuus) oils were 10% Novozym-435 (immobilized Candida antarctica lipase B) based on oil weight, alcohol to oil molar ratio of 4:1 at 50 °C for 8 h. The maximum conversions achieved using propan-2-ol were 92.8, 91.7 and 93.4% from crude jatropha, karanj and sunflower oils, respectively. Reusability of the lipase was maintained over 12 repeated cycles with propan-2-ol while it reached to zero by 7th cycle when methanol was used as an acyl acceptor, under standard reaction conditions. Revisions requested 22 December 2005; Revisions received 26 January 2006  相似文献   

3.
Biodiesel (fatty acids alkyl esters) is a promising alternative fuel to replace petroleum-based diesel that is obtained from renewable sources such as vegetable oil, animal fat and waste cooking oil. Vegetable oils are more suitable source for biodiesel production compared to animal fats and waste cooking since they are renewable in nature. However, there is a concern that biodiesel production from vegetable oil would disturb the food market. Oil from Jatropha curcas is an acceptable choice for biodiesel production because it is non-edible and can be easily grown in a harsh environment. Moreover, alkyl esters of jatropha oil meet the standard of biodiesel in many countries. Thus, the present paper provides a review on the transesterification methods for biodiesel production using jatropha oil as feedstock.  相似文献   

4.
The enhancing effect of various concentrations of 18 oils and a silicon antifoam agent on erythromycin production by Saccharopolyspora erythraea was evaluated in a complex medium containing soybean flour and dextrin as the main substrates. The oils used consisted of sunflower, pistachio, cottonseed, melon seed, water melon seed, lard, corn, olive, soybean, hazelnut, rapeseed, sesame, shark, safflower, coconut, walnut, black cherry kernel and grape seed oils. The biomass, erythromycin, dextrin and oil concentrations and the pH value were measured. Also, the kinds and frequencies of fatty acids in the oils were determined. The productivity of erythromycin in the oil-containing media was higher than that of the control medium. However, oil was not suitable as a main carbon source for erythromycin production by S. erythraea. The highest titer of erythromycin was produced in medium containing 55 g/l black cherry kernel oil (4.5 g/l). The titers of erythromycin in the other media were also recorded, with this result: black cherry kernel > water melon seed > melon seed > walnut > rapeseed > soybean > (corn = sesame) > (olive = pistachio = lard = sunflower) > (hazelnut = cotton seed) > grape seed > (shark = safflower = coconut). In media containing various oils, the hyphae of S. erythraea were longer and remained in a vegetative form after 8 days, while in the control medium, spores were formed and hyphae were lysed.  相似文献   

5.
When tomato leaves were sprayed with 0.1% emulsified canola oil, corn oil, grape seed oil, peanut oil, safflower oil, soya bean oil or sunflower oil, the severity of powdery mildew caused by Oidium neolycopersici was greatly reduced. Among these edible oils tested, sunflower oil was the most effective in the control of powdery mildew. When sprayed with 0.5% sunflower oil, powdery mildew on tomato leaves was reduced to a negligible level. Sunflower oil applied to halves of upper leaf surface did not induce resistance against the pathogen in the non‐treated halves. When applied to halves of lower leaf surface, it also failed to reduce the severity of powdery mildew on the upper leaf surface right above the treated area indicating that control of the powdery mildew by sunflower oil did not result from activation of host defence mechanisms. Scanning electron microscopy showed that control of powdery mildew with sunflower oil resulted mainly from the inhibition of conidial germination and suppression of mycelial growth of the pathogen.  相似文献   

6.
Preparation of biodiesel from crude oil of Pongamia pinnata   总被引:14,自引:0,他引:14  
Biodiesel was prepared from the non-edible oil of Pongamia pinnata by transesterification of the crude oil with methanol in the presence of KOH as catalyst. A maximum conversion of 92% (oil to ester) was achieved using a 1:10 molar ratio of oil to methanol at 60 degrees C. Tetrahydrofuran (THF), when used as a co-solvent increased the conversion to 95%. Solid acid catalysts viz. Hbeta-Zeolite, Montmorillonite K-10 and ZnO were also used for this transesterification. Important fuel properties of methyl esters of Pongamia oil (Biodiesel) compare well (Viscosity = 4.8 Cst @ 40 degrees C and Flash point = 150 degrees C) with ASTM and German biodiesel standards.  相似文献   

7.
Pongamia (Millettia pinnata) has been widely studied as a potential feedstock for biodiesel fuel, though little is known about its feasibility at a commercial level. Capital budgeting and cash flow analysis was conducted for a potential Pongamia plantation and crushing plant in Queensland, Australia. For annual seed yields ranging from 20 to 80 kg (in shell) per tree, the delivered cost of Pongamia oil was estimated to be between AUD $2.22 and AUD $0.64 per litre. The seed yield range of 20 to 80 kg per tree is roughly equivalent to between 7 and 29 t per hectare at a planting density of 357 trees per hectare. Major components of the delivered cost of (Pongamia) oil are the capital expenses of land acquisition, plantation establishment and the crushing plant construction. The major operational costs include mechanical harvesting; fertiliser; control of weed, pests and diseases; seed crushing; and freight of oil to a refinery. The cost items with the greatest volume sensitivity are the capital expenses, overheads (consisting mostly of salaries and wages of employees) and the expenses associated with harvesting and crushing operations. These costs could be significantly reduced if the seed yield could be increased. Several scenarios were tested to demonstrate the effect of seed yield and oil price on the profitability and cash flow of the Pongamia enterprise. At most plausible oil prices and seed yields, Pongamia oil is not expected to be economically viable.  相似文献   

8.
The non-edible plant Jatropha curcas L. is one of the most promising feedstock for sustainable biodiesel production as it is not a source of edible vegetable oils, produces high amounts of oil (approx. 30–60% in dry seeds) and does not require high-cost maintenance. However, as with other undomesticated crops, the cultivation of J. curcas presents several drawbacks, such as low productivity and susceptibility to pests. Hence, varietal improvement by genetic engineering is essential if J. curcas is to become a viable alternative source of biodiesel. There is to date no well-established and efficient transformation system for J. curcas. In this study, we tested various physical wounding treatments, such as sonication and sand-vortexing, with the aim of developing an efficient Agrobacterium-mediated transformation for J. curcas. The highest stable transformation rate (53%) was achieved when explants were subjected to 1 min of sonication followed by 9 min of shaking in Agrobacterium suspension. The transformation frequency achieved using this protocol is the highest yet reported for J. curcas.  相似文献   

9.
A comparative study on the composition, biodiesel production and fuel properties of non-edible oils from Euphorbia lathyris L. (EL), Sapium sebiferum L. (SS), and Jatropha curcas L. (JC) was conducted. Under optimal conditions, the FAME content and yield of the three oils were greater than 97.5 wt.% and 84.0%, respectively. The best biodiesel was produced from EL due to its high monounsaturation (82.66 wt.%, Cn: 1), low polyunsaturation (6.49 wt.%, Cn: 2, 3) and appropriate proportion of saturated components (8.78 wt.%, Cn: 0). Namely, EL biodiesel possessed a cetane number of 59.6, an oxidation stability of 10.4 h and a cold filter plug point of -11 °C. However, the cetane number (40.2) and oxidative stability (0.8 h) of dewaxed SS kernel oil (DSSK) biodiesel were low due to the high polyunsaturation (72.79 wt.%). In general, the results suggest that E. lathyris L. is a promising species for biodiesel feedstock.  相似文献   

10.
Cleome viscosa, an annual herb locally known as Jakhiya, grows naturally from seed in rainfed agricultural land and abandoned crop fields at altitudes ranging from 500 to 1500 m in scattered pockets of the Garhwal Himalaya. The seeds are mostly used as condiment. This species is a good substitute of cumin (Cuminum cyminum). Traditionally it is also used to cure a variety of diseases. It provides, three times higher yield when maintained by the farmers as a pure crop compared to yield obtained in mixed cropping conditions. With other food commodities, it is exchanged by the traditional farmers of Garhwal with the people of the areas where it does not grow. Because of its increasing demand, it is being sold in the market and is gaining more and more popularity. Until now no systematic attempt has been made to study the ecological significance and economic potential of Cleome viscosa. This paper describes the agronomy, yield, cost-benefit analysis, uses, and ethnobotany of Cleome viscosa. Systematic efforts are needed to promote its cultivation on a larger scale in village community degraded land and in marginal agricultural land where traditional crops grow with difficulty.  相似文献   

11.
Biodiesel is an alternative to petroleum-based conventional diesel fuel and is defined as the mono-alkyl esters of vegetable oils and animal fats. Biodiesel has been prepared from numerous vegetable oils, such as canola (rapeseed), cottonseed, palm, peanut, soybean and sunflower oils as well as a variety of less common oils. In this work, Moringa oleifera oil is evaluated for the first time as potential feedstock for biodiesel. After acid pre-treatment to reduce the acid value of the M. oleifera oil, biodiesel was obtained by a standard transesterification procedure with methanol and an alkali catalyst at 60 degrees C and alcohol/oil ratio of 6:1. M. oleifera oil has a high content of oleic acid (>70%) with saturated fatty acids comprising most of the remaining fatty acid profile. As a result, the methyl esters (biodiesel) obtained from this oil exhibit a high cetane number of approximately 67, one of the highest found for a biodiesel fuel. Other fuel properties of biodiesel derived from M. oleifera such as cloud point, kinematic viscosity and oxidative stability were also determined and are discussed in light of biodiesel standards such as ASTM D6751 and EN 14214. The (1)H NMR spectrum of M. oleifera methyl esters is reported. Overall, M. oleifera oil appears to be an acceptable feedstock for biodiesel.  相似文献   

12.
Production of biodiesel from edible plant oils is quickly expanding worldwide to fill a need for renewable, environmentally-friendly liquid transportation fuels. Due to concerns over use of edible commodities for fuels, production of biodiesel from non-edible oils including microbial oils is being developed. Microalgae biodiesel is approaching commercial viability, but has some inherent limitations such as requirements for sunlight. While yeast oils have been studied for decades, recent years have seen significant developments including discovery of new oleaginous yeast species and strains, greater understanding of the metabolic pathways that determine oleaginicity, optimization of cultivation processes for conversion of various types of waste plant biomass to oil using oleaginous yeasts, and development of strains with enhanced oil production. This review examines aspects of oleaginous yeasts not covered in depth in other recent reviews. Topics include the history of oleaginous yeast research, especially advances in the early 20th century; the phylogenetic diversity of oleaginous species, beyond the few species commonly studied; and physiological characteristics that should be considered when choosing yeast species and strains to be utilized for conversion of a given type of plant biomass to oleochemicals. Standardized terms are proposed for units that describe yeast cell mass and lipid production.  相似文献   

13.
Phenotypic variation of important seed traits like seed length, seed breadth, seed thickness, 100 seed weight and seed oil content were recorded in a total of 157 collected accessions of Pongamia. Out of these, fatty acid profiles of 38 accessions selected based on their high and low oil content was analyzed. Fatty acid profile revealed high variability in stearic, oleic and linoleic acid which varied from 0.42 to 10.61 %, 34.34 to 74.58 %, and 7.00 to 31.28 % respectively. Variations in palmitic and linolenic acid were small. Iodine value, saponification number and cetane number (CN) of fatty acid methyl esters (FAME) of seed oil ranges from 186.99 to 201.25, 81.13 to 108.19 and 46.16 to 56.47 respectively. Fatty acid compositions, degree of unsaturation and CN are the important parameters, which are used to determine quality of FAME were used as biodiesel. Some of the Pongamia accessions identified were higher in oil content while some accessions showed higher degree of unsaturation and a few of them had CN values higher than 55. Genetic diversity analysis with six TE-AFLP primers generated a total of 334 bands out of which 174 (52.10 %) were polymorphic. The genetic similarity ranged from 0.11 to 0.47. These findings clearly showed high level of genetic diversity and all economically desirable traits were not present in a single genotype of Pongamia. All these traits could be selected from these CPTs and transfer to a single elite variety through selection and breeding programme and could be utilized for large scale multiplication and plantation to produce high quantity and quality biodiesel in future.  相似文献   

14.
Fatty acid composition and stability of vegetable oils have taken more attention as an essential source of biologically active compounds in a good balanced diet. The purpose of the study was to determine peroxide value, free fatty acids, unsaponifiable matter, total carotenoid content, iodine value and fatty acid composition of sunflower, rapeseed, mustard, peanut and olive oils. Rapeseed and peanut oils had the highest peroxide values, while sunflower oil had the lowest peroxide values. The free fatty acid value of the tested oils varied between 0.43 and 1.36% oleic. The peanut oil had the highest free acid value and the mustard oil had the lowest one. Total carotenoid contents of mustard and rape seed oil were higher than those of the other oils tested. Palmitic acid (C16:0), oleic acid (C18:1) and stearic acid (C18:0) were the common main fatty acid components of the vegetable oils tested. Followed by linoleic acid, the amount of oleic acid was the highest among other fatty acid components. Mustard oil had the highest erucic acid (C22:1) with the amount of 11.38%, indicating that it cannot be used for human consumption. Among the oils investigated, sunflower and mustard oils were more stable than rapeseed, peanut and olive oils.  相似文献   

15.
The importance of pollination services for insect-pollinated crops in general, and for the major biodiesel crops, such as Jatropha curcas L., in particular, is reviewed. The dependence of the major biodiesel feedstocks on pollinators ranges from almost zero to low dependence in soybean, through low to medium dependence in rapeseed, and up to high dependence in the African oil palm and in J. curcas. Currently, the basic requirement of J. curcas for pollination services is largely neglected. In light of the enormous scale of existing and future plantations of J. curcas, and of the effective pollination by native pollinators in most commercial crops, it is clear that the local insect fauna of any given habitat, on any continent, will not be able to satisfy the pollination requirements of any plantation, once it becomes established and starts blooming. It is suggested that the best way to address the pending catastrophe of severely reduced yields in J. curcas plantations that would result from reduced reproductive success would be to use honeybees as the prime pollinators, regardless of the pollination services provided by the local insect fauna. Basic research on the contribution of honeybees to the reproductive success of J. curcas should be carried out and used as a guideline for planning future provision of proper honeybee pollination services in any given plantation, characterized by its specific size, age, planting density, soil type, irrigation, fertilization, and climatic conditions.  相似文献   

16.
油菜作为优势能源作物的发展潜力与展望   总被引:12,自引:0,他引:12  
介绍了生物能源的发展趋势、国内外油菜生产、用途与发展潜力,应用油菜作为生物能源的现状、趋势与生物柴油加工技术,提出了我国加快优势能源作物发展的建议。  相似文献   

17.
《Process Biochemistry》2014,49(3):474-489
In the world, the evolution of biodiesel demand influences the global market of edible feedstocks, affecting their commercial prices and availability and consequently food security. Colombia as a tropical country has the potential of producing multiple oleochemical feedstocks including both edible and non-edible vegetable oils and animal fats. However, the oleochemical industry in the country is based on a small range of feedstocks. In this paper, five oleochemical feedstocks were selected according to comparative criteria of national availability, potential oleochemical derivatives, projected expansion, impact on food security and land requirements. This analysis allowed obtaining oil palm, maize, jatropha, castorbean, and microalgae as promissory feedstocks. Then, multiproduct biorefineries were developed and economically and environmentally assessed, according to their production features. Thus, it was stated that the proposed configurations were able to support the development of the oleochemical industry in Colombia providing sustainable alternatives, which supply a growing demand of biodiesel and other oleochemical derivatives.  相似文献   

18.
Methyl esters from vegetable oils have attracted a great deal of interest as substitute for petrodiesel to reduce dependence on imported petroleum and provide an alternate and sustainable source for fuel with more benign environmental properties. In the present study biodiesel was prepared from sunflower seed oil by transesterification by alkali-catalyzed methanolysis. The fuel properties of sunflower oil biodiesel were determined and discussed in the light of ASTM D6751 standards for biodiesel. The sunflower oil biodiesel was chemically characterized with analytical techniques like FT-IR, and NMR (1H and 13C). The chemical composition of sunflower oil biodiesel was determined by GC–MS. Various fatty acid methyl esters (FAMEs) were identified by retention time data and verified by mass fragmentation patterns. The percentage conversion of triglycerides to the corresponding methyl esters determined by 1H NMR was 87.33% which was quite in good agreement with the practically observed yield of 85.1%.  相似文献   

19.
The biodiesel processor was developed for the production of biodiesel from non-edible oil of jatropha and karanj. The newly developed biodiesel processor is suitable for farmers in village level biodiesel production. The biodiesel processor was capable of producing 15 kg biodiesel per batch in 1.5 h at reaction temperature of 60°C. The biodiesel was produced from raw jatropha and karanj oil, and its blends with diesel were tested for power generation in a 7.5-kVA diesel engine generator set. The fuel properties, namely, kinematic viscosity and specific gravity, were found within the limits of Bureau of Indian Standards specifications. The overall efficiency of the generator for 4,500 W loading condition of jatropha- and karanj-biodiesel-blended fuel were recorded in the range of 21–23% and 24–27%, respectively. The overall efficiency of the generator for 6,000 W loading conditions was improved for jatropha and karanj biodiesel blends and were found in the range of 31–33% and 33–39%, respectively. Biodiesel blends B80 and pure biodiesel of karanj produced more power, and maximum overall efficiency was recorded as compared with diesel fueled generator. The overall efficiency on jatropha-biodiesel-blended fuel were found less than the diesel-fueled generator. The biodiesel processor based on alkali-catalyzed transesterification process can be used for quality biodiesel production from edible and non-edible vegetable oils. This processor can be integrated with rural energy system for domestic and small-scale industrial unit for biodiesel production.  相似文献   

20.
目前生物柴油因其环保和可再生利用资源的特性备受关注。多数生物柴油是通过甲醇和碱催化食用油得到的,而大量非食用油也可以制备生物柴油。本文报道用高含游离酸脂肪油快速高效低成本制备成其单酯的二步法工艺。先用1% H2SO4以少于1.5%量对甲醇和云南特产香果树(Lindera communis)籽的粗原料油以10∶1摩尔比组成的混合液酸催化酯化游离脂肪酸;之后再对醇和得到的油脂产品按摩尔比15∶1的混合液碱催化转化为单甲酯和甘油。本方法是一个直接甲脂化制备生物柴油的工艺简洁、降低成本的新技术。文中还讨论了该工艺影响转化效率的主要因素,如摩尔比,催化量,温度,反应时间和酸度。香果树生物柴油不重蒸,而其生物柴油的主要特性,如粘度、热值、比重、闪点、冷滤点等与生物柴油标准的匹配度,也做了报道,研究结果将为香果树生物柴油以非重蒸油料制备生物柴油产品,作为潜在的柴油燃料替代产品提供技术支撑。  相似文献   

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