首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
以麻疯树油、亚麻油、乌柏油为原料油,采用固定化脂肪酶Lipozyme TL IM,在3.0 g油、1 mL正己烷、醇油摩尔比为3.5∶1、固定化酶质量为油质量20%的条件下进行生物柴油的制备,通过脂肪酸甲酯产率和组成分析,以考察生物柴油制备的影响因素,进行反应时间优化.结果表明,酶的催化作用对脂肪酸组分不存在选择性,且...  相似文献   

2.
非食用油脂作为一种生产可再生烃类燃料的原料,受到了全世界的关注。相对于常规的裂解非食用油脂生产烃类燃料的方法中存在的脱羧选择性较差、产物中饱和烃类少、含氧有机物多等问题,微波辅助裂解具有选择性、脱羧过程中微波具有促进作用、烃类得率高等优点。本文简述了目前常用的油脂催化裂解的方法,着重介绍了不同催化剂的催化裂解、微波辅助裂解制备液体燃料。通过比较,得出了微波催化裂解在燃料性能及处理成本上的优势,为制备低成本、高效能的可再生烃类燃料提供了新方法,具有广阔的应用前景。  相似文献   

3.
Prafulla D. Patil 《Fuel》2009,88(7):1302-1306
The non-edible vegetable oils such as Jatropha curcas and Pongamia glabra (karanja) and edible oils such as corn and canola were found to be good viable sources for producing biodiesel. Biodiesel production from different edible and non-edible vegetable oils was compared in order to optimize the biodiesel production process. The analysis of different oil properties, fuel properties and process parameter optimization of non-edible and edible vegetable oils were investigated in detail. A two-step and single-step transesterification process was used to produce biodiesel from high free fatty acid (FFA) non-edible oils and edible vegetable oils, respectively. This process gives yields of about 90-95% for J. curcas, 80-85% for P. glabra, 80-95% for canola, and 85-96% for corn using potassium hydroxide (KOH) as a catalyst. The fuel properties of biodiesel produced were compared with ASTM standards for biodiesel.  相似文献   

4.
Palm oil is obtained from the fruit flesh ofElaeas guineensis. Whole bunches of ripe fruit are harvested and brought to the oil mill. Processing involves sterilization, mechanical removal of fruit from the bunch, and mechanical breakdown of the fruit structure followed by expression of the oil in a screw press. Oil mixed with water and fruit debris is purified in settling tanks and centrifuges, dried and stored. Oil yield represents 22% of the fresh fruit bunch and kernels a further 5%. The solid wastes are the empty fruit bunch, the press fiber and the nut shells. Empty bunches are incinerated, while fiber and shell are used to fire the mill boilers. The liquid effluents are mixed and usually treated by anaerobic/aerobic fermentation until fit for discharge. Various treatment systems are described. Quality control in the oil mill concentrates on (a) minimizing deterioration of the oil by hydrolysis and by oxidation, and (b) optimizing oil yield by frequent measurements of oil losses.  相似文献   

5.
Annona squamosa- and Pongamia glabra-based polyesteramides (ASPEA and PGPEA) have been reported as corrosion protective coatings. To improve their film properties such as curing, physico-mechanical and anticorrosive properties further, post-vinylation of these resins with styrene and vinyl acetate monomer in varying ratio (4:1, 3:1 and 2:1) was carried out in the presence of free radical initiator (benzoyl peroxide). The incorporation of styrene and vinyl acetate in ASPEA/PGPEA was confirmed by FTIR and 1H NMR spectral techniques. Physico-chemical, physico-mechanical and anticorrosive properties were studied by standard methods. Thermal stability and curing behaviour of vinylated ASPEA/PGPEA was studied by thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. It has been observed that vinylation of these resins improves the curing, physico-mechanical and anticorrosive performance of ASPEA/PGPEA films. Among all 2:1 ASPEA/PGPEA:styrene/vinyl acetate ratio exhibited best results.  相似文献   

6.
Linolenic acid of more than 95% purity was produced by liquid-liquid extraction of linseed oil fatty acids with wet furfural and hexane in a Podbielniak centrifugal extractor. The minimum ratio of furfural to linseed acids to obtain this purity was 10 to 1. There was no significant change in product purity for solvent ratios between 10 and 15, operating temperatures from 90° to 110°F., and furfural moisture contents between 1.0 and 2.8%. When the solvent ratio is reduced to 8 or the furfural moisture to 0.2%, purity decreases. Oxidation of linseed acids before extraction also results in decreased separation. An estimate based on pilotplant data indicates a “cost to make” (excluding administrative and selling expenses, profit, income taxes, and interest on investment) of 18.0 cents per pound of 97% linolenic acid for a process which includes hydrolyzing linseed oil, separating the fatty acids by liquid-liquid extraction, recovering solvents by distillation, and distilling the fatty acid products. Potential uses for linolenic acid are reviewed.  相似文献   

7.
齐亚平  刘虎在 《现代化工》2014,34(11):125-126
以煤间接液化轻质馏分油为原料,采用特种油催化剂通过一段高压加氢法生产优质特种溶剂油,特种油产品的烯烃质量分数1.25%,总硫质量分数0.05×10-6,芳烃体积分数0.1%,基本能满足特种油指标要求。  相似文献   

8.
In the present work, the transesterification of non-edible oil with methanol and ethanol is studied. The reactor phase transitions are directly observed in a double windowed cylindrical reactor and the conversion to fatty esters is measured. The optimization of the process conditions was carried out based on a statistical design of experiments where the key process variables were studied over different ranges to obtain a reliable model for the efficiency of the reaction as a function of reaction time, temperature, pressure and alcohol to oil molar ratio. From direct observations and the modeling of the phase behavior, a better understanding of the supercritical alcohol transesterification process is obtained as well as the confirmation of the phase equilibrium predictions based on the GCA-EOS model.  相似文献   

9.
Methyl sterculate was rearranged by use of 0.5% of rhodium catalyst to isomeric conjugated diene fatty acid methyl esters containing both methylene-and methyl-branched isomers. The rearanged products were hydrogenated directly to saturated, methyl-substituted, branched-chain fatty acid methyl esters with the methyl substituent at one of the positions formerly occupied by the cyclopropenoid ring. The crude branched-chain fatty acids from these esters were purified by recrystallization from a mixed solvent of ethanol and water (80:20, v/v) and flash distillation; the product contained about 90% of branched-chain fatty acids (C19:80%, C18:10%). Esters of the branched-chain fatty acid were prepared with 2-ethylhexyl alcohol or trimethylolpropane, and the characteristic properties of these esters were investigated. The branched-chain fatty esters appear to have potential utility in lubricants; other uses may be possible. Presented at the AOCS meeting in New Orleans, May 1981.  相似文献   

10.
Conventional treatment of complex fractures includes the use of plates and nails, which may compromise the affected limb's functionality. Previous studies have demonstrated promising results through chemical, mechanical, and cytotoxicity tests of a chitosan-based adhesive—proposed as a new method to bond high energy fractures—in dry environments with adequate adhesion, malleability, and biocompatibility. In this study, we focused on performing an evaluation of bio-adhesives’ mechanical properties and bone-adhesive joint using two chitosan-based formulations (with and without a cross-linking agent). The texture profile analysis determined adhesive properties, such as cohesiveness, adhesiveness, hardness, and resilience at different cure times. Bone-adhesive joint was evaluated according to the tensile bond strength test and shear bond strength test. Fracture toughness and cohesive strength were calculated through a rigid double cantilever beam test at mode I failure. Bone-adhesive joints were tested in two environments: dry and submersed in water at 37 °C for 1, 6, and 24 h (curing time), an approximation of surgery conditions. The experimental results showed an incremental of adhesiveness and hardness of the cross-linked adhesive during the first 15 min, which was determined as the usage time to spread on the bone fracture. The joint interaction between the adhesive and bone surfaces was studied; chitosan-based formulations showed an adhesive joint failure under dry conditions in most of the cases. However, this behavior changed under aqueous conditions, presenting cohesive failures. Under aqueous conditions, cross-linked bone-adhesive presented an augmented tensile bond strength up to 0.024 ± 0.0036 MPa, a shear bond strength up to 0.031 ± 0.0069 MPa, and fracture toughness of 2.38 ± 0.54 J/m2 was observed with a cure time of 24 h. Finally, the presence of the cross-linking agent in the cross-linked bio-adhesive reduced the sensitivity of the adhesive to water; a promising finding that should be explored in future studies.  相似文献   

11.
Simple alkyl FA esters have numerous uses, including serving as biodiesel, a fuel for compression ignition (diesel) engines. The use of acid-catalyzed esterification for the synthesis of FAME from acid oil, a by-product of edible vegetable oil refining that is produced from soapstock, was investigated. Soybean acid oil contained 59.3 wt% FFA, 28.0 wt% TAG, 4.4 wt% DAG, and less than 1% MAG. Maximum esterification occurred at 65°C and 26 h reaction at a molar ratio of total FA/methanol/sulfuric acid of 1∶15∶1.5. Residual unreacted species under these conditions, as a fraction of their content in unesterified acid oil, were FFA, 6.6%; TAG, 5.8%; and DAG, 2.6%. This corresponds to estimated concentrations of FFA, 3.2%; TAG, 1.3%; and DAG, 0.2%, on a mass basis, in the ester product. In an alternative approach, the acylglycerol species in soapstock were saponified prior to acidulation. High-acid (HA) acid oil made from this saponified soapstock had an FFA content of 96.2 wt% and no detectable TAG, DAG, or MAG. Optimal esterification conditions for HA acid oil at 65°C were a mole ratio of FFA/methanol/acid of 1∶1.8∶0.17, and 14 h incubation. FAME recovery under these conditions was 89% of theoretical, and the residual unesterified FFA content was approximately 20 mg/g. This was reduced to 3.5 mg/g, below the maximum FFA level allowed for biodiesel, by washing with NaCl, NaHCO3, and Ca(OH)2 solutions. Alternatively, by subjecting the unwashed ester layer to a second esterification, the FFA level was reduced to less than 2 mg/g. The acid value of this material exceeded the maximum allowed for biodiesel, but was reduced to an acceptable value by a brief wash with 0.5 N NaOH.  相似文献   

12.
研究了用溶剂辅助糠醛精制废润滑油,提高润滑油的收率,同时改善了产品质量.通过筛选得出助溶剂正丁醇的最佳加入量,考察了精制温度和剂油比对产物收率的影响.对产物进行性质测定结果表明:在糠醛溶剂中加入15%(正丁醇:糠醛)的正丁醇、精制温度85℃和剂油比为2:1的条件下,得到再生后润滑油基础油为澄清淡黄色,产物收率为88.5...  相似文献   

13.
Enzymatic esterification and supercritical fluid extraction was used to produce phytosterol esters from soybean oil deodorizer distillates. The raw material was first subjected to a two‐step enzymatic reaction; the product obtained mainly comprised fatty acid ethyl esters, tocopherols and phytosterol esters, together with minor amounts of squalene, free fatty acids, free sterols and triacylglycerols. The phytosterol esters were then purified from this mixture using supercritical carbon dioxide. Experimental extractions were carried out in an isothermal countercurrent column (without reflux), with pressures ranging from 200 to 280 bar, temperatures of 45–55 °C and solvent‐to‐feed ratios from 15 to 35 kg/kg. Using these extraction conditions, the fatty acid esters were completely extracted and, thus, the fractionation of tocopherols and phytosterol esters was studied. At 250 bar, 55 °C and a solvent‐to‐feed ratio of 35, the phytosterol esters were concentrated in the raffinate up to 82.4 wt‐% with satisfactory yield (72%).  相似文献   

14.
选用了非食用油麻疯果油为原料,以氢氧化钠、氢氧化钾、甲醇钠为催化荆,通过酯交换法制取生物柴油,研究表明最适宜工艺条件为:醇油比6:1,反应温度60℃,反应时间80min,搅拌强度为600 r/min,催化剂用量为1.2%,转化率达到97%以上,且生物柴油各项理化指标均符合美国和德国测试标准.且从麻疯果的种植到生物柴油的生产整个产业链出发,其原料成本更低,经济效益更大,体现了不与粮争地的优势.  相似文献   

15.
The production of sophorose lipids increased with increasing concentrations of both safflower oil and glucose, and was profoundly influenced by the concentration of yeast extract. A high concentration of sophorose lipids (about 135 g/L) was obtained (in a 1-L Bellco stirred reactor) when the medium consisted of 10% glucose, 10.5% safflower oil, 0.1% urea, and 0.25–0.3% yeast extract. A similar yield of sophorose lipids also was obtained in a 20-L bioreactor. About 50% of the apolar sophorose lipid 1′,4″-lactone 6′,6″-diacetate (SL-1) was found in the mixture of sophorose lipids produced under these conditions.  相似文献   

16.
Jibrail Kansedo  Subhash Bhatia 《Fuel》2009,88(6):1148-1150
This paper explores the feasibility of converting Cerbera odollam (sea mango) oil into biodiesel. The first part of this study focused on the extraction of oil from the seeds of C. odollam fruits, whereas the second part focused on the transesterification of the extracted oil to fatty acid methyl esters (FAME). The transesterification reactions were carried out using three different catalysts; sodium hydroxide (NaOH) as a homogenous catalyst, sulfated zirconia alumina and montmorillonite KSF as heterogeneous catalysts. The seeds were found to contain high percentage of oil up to 54% while the yield of FAME can reach up to 83.8% using sulfated zirconia catalyst.  相似文献   

17.
Production of hydrocarbons by pyrolysis of methyl esters from rapeseed oil   总被引:7,自引:0,他引:7  
The pyrolysis of a mixture of methyl esters from rapeseed oil has been studied in a tubular reactor between 550 and 850°C and in dilution with nitrogen. A specific device for the condensation of cracking effluents was used for the fractionated recovery of liquid and gaseous effluents, which were analyzed on-line by an infrared analyzer and by gas chromatography. The cracking products in the liquid effluent were identified by gas chromatography/mass spectrometry coupling. The effects of temperature on the cracking reaction were studied for a constant residence time of 320 ms and a constant dilution rate of 13 moles of nitrogen/mole of feedstock. The principal products observed were linear 1-olefins,n-paraffins, and unsaturated methyl esters. The gas fraction also contained CO, CO2, and H2. The middle-chain olefins (C10–C14 cut) and short-chain unsaturated esters, produced with a high added value, had an optimum yield at a cracking temperature of 700°C.  相似文献   

18.
In view of the increasing interest in the use of residues from the food industry as source for packing applications, the by‐product of the mechanical extraction of avocado oil is an attractive product as it consists basically a hydrated and defatted pulp, rich in proteins, fibers. and oil. This work aims to produce biobased polymer films from avocado oil extraction residue. Seven film‐forming solutions were elaborated from puree and the additives tested were glycerol, cassava starch, and microcrystalline cellulose. The films obtained from the pure residue presented brittle behavior. All films presented low values of water vapor permeability (0.064 to 0.446 g mm m?2·kPa?1 h?1) and medium water soluble fraction (43.79 to 56.92%). The films with cassava starch and glycerol presented the best results, with mechanical (tensile: 2.70 MPa; elongation: 13.7%) and thermal properties in the range typically found in the literature for biobased films. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43957.  相似文献   

19.
The use of methyl acetate instead of methanol for supercritical synthesis of glycerol-free biodiesel from vegetable oils is a new process and its study is very limited in the literature. In this work, it has been tested for the first time on three edible and non-edible oils with different fatty acid composition. The process was also applied to waste oil with higher free fatty acid (FFA) content. The results demonstrate that the oil composition does not significantly influence the biodiesel yield.The influence of temperature, pressure and molar ratio of reactants was studied. All the oils achieved complete conversion after 50 min at 345 °C, 20 MPa with methyl acetate:oil molar ratio equal to 42:1. The obtained data also allowed calculating the apparent rate coefficients and activation energies.Eventually, some new information on the process was obtained. Thermal degradation of triacetin, which substitutes glycerol as the by-product of the transesterification reaction, was observed. Some indicative experiments were performed to understand the role of the acetic acid produced by FFA esterification.  相似文献   

20.
The bio-oil extracted from wild radish seeds is non-edible and it still remains an unexplored area in terms of its use as a feedstock for biodiesel. It was extracted from the seeds using mechanical expeller and the oil yield was found to be 46.2?±?2?wt%. The physical and chemical properties of the extracted oil were analyzed as per AOAC official methods. In this current study, biodiesel was derived by catalytic transesterification reaction. The parameters that influence the processes like methanol to oil molar ratio, catalyst concentration, reaction temperature, and reaction time were optimized. Taguchi statistical method and Analysis of Variance (ANOVA) table were used to understand the effects of the influencing parameters and to optimize the biodiesel yield. Further, it was compared with Box-Behnken Design (BBD) using Response Surface Methodology (RSM). It shows that Taguchi method gave similar results of RSM within a limited number of runs. At optimized condition, the yield of biodiesel was 94.58?wt%. Kinetic studies were also performed for transesterification reaction and it was observed that the reaction follows pseudo-first-order kinetics. The reaction rate constants and activation energy were determined. The physical and chemical properties of the biodiesel were analyzed as per ASTM test methods and compared with ASTM D6751 standard.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号