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1.
千年健挥发油微波辅助提取研究   总被引:1,自引:1,他引:1  
采用微波辅助溶剂萃取法(MASE)提取千年健挥发油,并利用GC-MS技术对其化学成分进行了分析。最佳提取条件为:石油醚作溶剂,微波功率600 W,提取温度60℃,提取时间25 min,在该条件下提取的挥发油共鉴定出63种成分,主要为芳樟醇(相对质量分数23.411%,下同),7-乙酰基-2-羟基-2-甲基-5-异丙基二环[4.3.0]壬烷(5.222%),4-松油醇(3.971%)。与传统水蒸气蒸馏法(HD)比较发现,MASE法节省时间,得率更高,同时化学组成成分差异不大,是一种完全可以替代HD法提取千年健挥发油的高效、节能的提取技术。  相似文献   

2.
超声强化提取薏苡仁油的研究   总被引:15,自引:0,他引:15  
研究了提取溶剂、提取温度、料液比、薏苡仁粒径、提取时间对超声提取薏苡仁油的影响。在单因素实验的基础上 ,进行了正交实验。结果表明 ,各因素对油提取率的影响次序为 :物料粒径 >超声提取温度 >超声提取时间 >超声频率和功率 >料液比。优化后的工艺参数为 :提取温度 50℃ ,物料粒径 60~ 80目 ,料液比 1∶3 5 ,超声功率和频率 2 5kHz、30 0W ,提取时间40min。  相似文献   

3.
A series of castor oil adducts were synthesized by esterification of castor oil with acid anhydrides: phthalic, maleic and succinic anhydrides. The chemical structure of castor oil and the prepared adducts were characterized by means of IR and 1H NMR spectroscopy. The number‐average and weight‐average molecular weights were measured by gel permeation chromatography. The electrical properties were studied through the permittivity, dielectric loss and conductivity measurements, which are considered to be in the range of electrical insulation. The electrical conductivity, which describes the ionic mobility of the systems, was found to be in the range of 10–9 to 1012 S/cm. This indicates that castor oil and its esters could be used for antistatic applications. The viscosity η and the activation energy Eη, obtained from the dependency of viscosity on temperature using the Arrhenius equation, were found to increase with increasing molecular weight of the system. The effect of different concentrations of castor oil and its esters on the growth activities of the sugar beet pathogens R. solani and S. rolfsii was studied through the determination of percent germination, average length of hyphal extensions, dry mass yield and the production of sclerotia. The obtained data indicate that the esterification of castor oil with anhydrides improves the antifungal activity.  相似文献   

4.
对溶剂萃取法修复石油类污染土壤的新技术做了较为全面的概述.首先,介绍了溶剂萃取技术的概念、机理和适用范围;其次,介绍了包括有机溶剂、表面活性剂、环糊精、超临界流体在内的萃取剂的研究进展;再次,阐述了影响溶剂萃取效率的因素和溶剂萃取的工艺条件;最后,对溶剂萃取技术的研究和应用做了展望.  相似文献   

5.
杨红强  丁明山  胡斌  任嗣利 《化工进展》2014,33(9):2495-2500,2516
开发了一种水辅助溶剂法从油砂中提取沥青的技术。该方法通过在油砂固相与有机溶剂间介入水层提取油砂中的沥青。以内蒙古扎赉特旗油砂矿为研究对象,考察了温度、剂砂质量比、提取时间、甲苯在复合溶剂中的含量及溶剂的种类与性质对沥青回收率高低的影响,结果表明:最佳提取条件为提取温度50℃,剂砂质量比1∶1,提取时间25min。沥青回收率与提取溶剂的性质紧密相关,水层介入有效降低了固体微粒组分在有机相中的含量,且便于后续的有机相与泥砂相的分离。通过对各种溶剂提取的沥青进行组分分析,发现各种溶剂对沥青提取能力的差异性源于溶剂的化学组成和结构不同。本文相关研究结果对溶剂法提取油砂中沥青技术及溶剂种类的选择具有指导作用。  相似文献   

6.
油砂沥青溶剂提取回收组合工艺   总被引:1,自引:0,他引:1  
采用有机溶剂提取-超临界CO2回收溶剂这一组合方法对加拿大Athabasca油砂进行了提取分离及溶剂回收实验,通过实验筛选出最佳抽提溶剂为重整汽油。溶剂提取的最佳工艺条件:提取温度80℃,溶剂流量60mL/min,提取时间60min。在此条件下油砂沥青提取率达到92.74%。对超临界CO2-重整汽油体系的相行为进行研究,并通过实验综合考察了温度、压力、CO2流量以及回收时间等工艺操作条件对溶剂回收的影响。结果表明:在回收温度50℃,回收压力13MPa,溶剂与CO2分离温度70℃,压力5MPa,CO2流量7.5L/h,时间1h的条件下,重整汽油的回收率为98.71%。  相似文献   

7.
R.K. Singh 《Fuel》2011,90(7):2538-4304
Bio-energy is now considered as having the potential to provide the major part of the projected renewable energy provisions of the future. Slow pyrolysis is one of the three main thermal routes, with gasification and combustion, for providing a useful and valuable bio-fuel. Slow thermal pyrolysis of castor seeds were carried out in a semi batch reactor made up of stainless steel at temperature range from 450 °C to 600 °C to produce bio-fuel. This paper studied the effect of temperature on pyrolysis of castor seeds to find the optimum temperature of maximum liquid yield. The thermal degradation temperature of castor seed was studied using thermo gravimetric analysis (TGA) at a heating rate of 20 °C/min in air atmosphere. The oil samples obtained at optimum condition is analyzed according to their fuel properties, elemental analysis, functional group presents, and compounds presents.  相似文献   

8.
New inorganic-organic hybrids were synthesized through the reaction of castor oil (CO) or epoxidized castor oil (ECO) with tetraethoxysilane (TEOS). The mass proportions of ECO/TEOS varied from 90∶10 to 60∶40, and films of the material were thermally cured. An IR spectroscopy analysis was performed, and macro- and microscopic properties such as adhesion, hardness, swelling in toluene, microstructure (scanning electron microscopy), and T g were investigated as a function of the proportion of their inorganic-organic precursor. Morphologic studies showed that the hybrid films were homogeneous when lower proportions of the inorganic precursors were used. Hardness and tensile strength increased with TEOS concentration, whereas swelling in toluene decreased with TEOS concentration. Good adhesion was observed throughout the hybrid series.  相似文献   

9.
对加拿大油砂进行了溶剂抽提分离试验,考察了石油醚、石脑油、甲苯、环己烷以及重整汽油对提取效果的影响,确定重整汽油为最佳抽提溶剂.综合考察了提取温度、溶剂与油砂体积比、提取时间以及搅拌速度等工艺操作条件对油砂沥青提取的影响,结果表明,在提取温度500℃,溶剂和油砂的体积比为1∶1,提取时间60 min,搅拌速度为80 r/min的条件下,油砂沥青提取率达到92.57%.  相似文献   

10.
The diffusion coefficient of rapeseed oil was determined from data obtained during time-varied solvent extraction experiments. The experiments were carried out in a Gülbaran extractor-diffuser with hexane as the solvent. A relationship was found between the slope of the diffusion line and the shape and size of the rapeseed particles. This relation can be used to calculate the diffusion coefficient. A diffusion coefficient of 3.4×10−8 cm2/s was determined from the experimental data.  相似文献   

11.
A new, rapid method for total oil analysis of soybeans is proposed in which ground soybeans are mixed with solvent and further ground in a closed homogenizer until the oil is completely dissolved. A sample of the slurry can then be filtered and the oil content determined by evaporating the solvent from a measured amount of miscella. Parameters studied included times and speeds needed to produce sufficiently small particles so that all the oil was dissolved. The new analysis compared favorably with conventional Goldfisch extraction for total oil of soybeans. Preliminary experiments indicated that rapeseed could be extracted by the new procedure without preliminary grinding. Published with the approval of the director of the Arkansas Agricultural Experiment Station.  相似文献   

12.
轻质油品溶剂萃取脱硫技术研究   总被引:3,自引:0,他引:3  
刘章勇  张玉贞  张小英  刘东 《应用化工》2009,38(7):1067-1072
综述了目前国内外轻质油品溶剂萃取脱硫的相关技术,并进行比较和评价。认为单一的溶剂萃取脱硫技术存在着碱液排放量大、脱硫率不高的问题,多种脱硫技术相结合是深度脱硫的发展趋势。离子液体由于可以循环使用,必将是一项非常有发展前途的脱硫技术。  相似文献   

13.
王本庭  钱俊峰  刘森  云志 《化工学报》2007,58(10):2636-2640
以双液相萃取技术处理棉籽,在得到脱毒棉粕的同时得到含有高质量毛油的非极性相。以非极性相作为与甲醇进行酯交换反应的原料,得到脂肪酸甲酯和甘油。考察了非极性相溶剂石油醚与棉籽油的比例对酯交换转化率和洗涤粗产品用水量的影响,确定了石油醚与棉籽油的最佳质量比为3,在此条件下,洗涤用水量可降低一半。考察了醇油比、催化剂用量、反应温度、反应时间等参数对转化率的影响。应用正交实验的方法找出酯交换反应的适宜条件为:醇油比6:1,催化剂用量1.1%,反应温度60℃,反应时间120min。在此反应条件下,产物中脂肪酸甲酯的含量可达97.4%。  相似文献   

14.
This short communication reports an assessment of the oxidation process of castor oil fatty methyl ester samples submitted to Rancimat (EN 14112) and PetroOXY (ASTM-D7545) oxidation methods. Fourier Transformed Infrared Spectroscopy (FTIR) was used to evaluate the FAME degradation products resulting from the accelerated oxidation, following the area of the carbonyl band (~ 1740 cm−1) of the samples at different oxidation times. Our results indicate that the level of oxidation of castor oil FAME, using the Rancimat method, follows a similar pattern of the oxidized samples using the PetroOXY method.  相似文献   

15.
The influence of the two contact modes, percolation and immersion, during the extraction of oilseeds by means of a solvent are presented. Experiments were performed in lab-scale equipment with soybean flakes, arranged in beds that reproduce these two contact modes. The extractions were carried out with hexane at constant temperature. To simulate the performance of shallow-and deep-bed extractors, two different bed height/diameter ratios were used. The experimental results are explained in terms of the basic transfer phenomena that occur during extraction. These phenomena are addressed to develop a mathematical model, which is used to simulate extraction under both contact modes. The immersion scheme yielded greater efficiency than the percolation mode to extract soybean flakes for the two bed height/diameter ratios studied. The mathematical model predicts very well the experimental findings. It also predicts the solvent retained by the solid mass after extracting the oil.  相似文献   

16.
This paper describes the extraction of borage seed oil by supercritical carbon dioxide (SC-CO2) and the further extraction of antioxidants from the SC-CO2-defatted borage meal with organic solvents (water, methanol, ethanol and ethyl acetate). The optimal conditions for oil extraction were obtained at 303 and 323 K at 200 bar, 2.5 h and a continuous flow of CO2 of 1.5 L/h introduced through the bottom when the operating pressure and temperature were reached, attaining a yield of 60%. Borage oil is rich in unsaturated fatty acids; oleic acid, linoleic acid and linolenic acid accounted for 74% of the total fatty acid content under the above conditions. The highest extraction yield was achieved using water or methanol as extracting solvent from the SC-CO2-defatted borage meal at 303 K and pressures of 200 and 150 bar for water and methanol, respectively. The most potent extracts, according to all methods tested, were obtained with water and methanol.  相似文献   

17.
Modeling solvent extraction of vegetable oil in a packed bed   总被引:1,自引:0,他引:1  
A one-dimensional model was developed for solvent extraction of oil from a packed bed of oil-bearing vegetable materials. The equilibrium relationship between the residual oil content of marc and oil concentration of stagnant miscella in pores of the bed material was generated through experiments with rice bran and hexane. The nondimensional parameters recognized from the model describing extraction were initial Reynolds number (Rei), initial Schmidt number (Sci), bed void fraction (εb), particle porosity (εp), ratio of bed diameter to particle diameter (Dt/dp), ratio of bed depth to bed diameter (L/Dt), ratio of particle surface area to bed cross-section (apAL/A=apL), and recycle of solvent and equilibrium distribution coefficient (EDC). For reducing the time required to extract to the same residual oil content of marc, higher values of Rei, εb, and apL were beneficial, whereas higher values of Sci, εp, Dt/dp, L/Dt, and EDC were detrimental.  相似文献   

18.
A one-step procedure for the preparation of (E)-2-nonenal from commercial castor oil by ozonolysis in acetic acid, followed by exposure of the resulting intermediate product top-toluene sulfonic acid, is described. The manufactured aldehyde is of high purity and the method, by virtue of being simple and using inexpensive raw material, has advantages over those reported in the literature.  相似文献   

19.
Palm carotene was successfully concentrated from crude palm oil (CPO) by a batch adsorption process using a synthetic (polymer) adsorbent followed by solvent extraction. Carotene was concentrated to about 20,000 ppm, or about 33.3 times the original concentration in CPO. Carotene recovery varied from 16 to 74% depending on the process conditions. Adsorption times, isopropanol (IPA) extraction times, temperatures of adsorption and solvent extraction process, effect of agitation during IPA extraction process, and adsorbent lifespan were evaluated to determine their effects on the percentage of carotene extracted and carotene concentration. The minimum adsorption time required was 0.5 h. However, an adsorption time of 1.5 h gave a significantly higher carotene concentration than adsorption times of 0.5, 1.0, and 0.2 h. The IPA extraction time was determined based on the final carotene concentration desired. The suitable temperature for adsorption and solvent extraction process was 40°C. There was no significant difference in the percentage of carotene extracted and carotene concentration between the IPA extraction process with and without agitation.  相似文献   

20.
A new norbornenyl-functionalized castor oil alcohol (NCA) was synthesized and ring-opening metathesis copolymerized separately with two norbornene-based cross-linking agents: dicyclopentadiene (DCPD) and a bifunctional norbornene crosslinker (CL). Isothermal differential scanning calorimetry (DSC) was used to examine the cure behavior of NCA/DCPD and NCA/CL resins, through which a reasonable cure schedule was determined. The glass transition temperature (Tg) and storage modulus (E′), characterized by dynamic mechanical analysis (DMA), increased significantly in both copolymer systems with the addition of cross-linking agents. Cross-link density of the two systems was evaluated using a modified empirical equation from the kinetic theory of rubber elasticity. Differences in tensile stress-strain behavior and thermal stability between polymerized NCA/DCPD and NCA/CL were correlated to the structural rigidity and cross-linking density resulting from the cross-linking agents.  相似文献   

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