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1.
超临界CO2流体萃取肉桂油的研究   总被引:3,自引:0,他引:3  
高鹏飞  尹爱武  赖小平  蒋东旭 《广州化工》2009,37(6):107-108,117
优选萃取肉桂油的工艺条件,分别采用水蒸汽蒸馏法和SFE—CO2提取肉桂油,进行SFE—CO2萃取肉桂油的正交试验,优选最佳萃取条件。由实验可知,SFE—CO2萃取肉桂油主要成分桂皮醛的得率大于水蒸汽蒸馏法,其最佳萃取条件为:萃取温度45℃,萃取压力20MPa,萃取时间2.5h。应用SFE—CO2萃取肉桂油,萃取率高,操作纯净,是具有相当发展潜力的提取分离方法。  相似文献   

2.
Portulaca oleracea (purslane) seed oil is a rich source of omega-6 and omega-3 fatty acids. Extraction of the purslane seed oil while preserving its high nutritive quality has been a challenge since conventional solvent extraction has many adverse effects on bioactive content. This study aims the optimization of purslane seed oil supercritical fluid extraction (SFE) conditions and to compare purslane seed oils obtained with SFE and conventional solvent extraction in terms of oil yield, along with the purslane seed oil quality and bioactive content. For this purpose, the SFE process parameters (pressure, temperature, static time, and dynamic time) are optimized for oil yield, omega-6, omega-3, and antioxidant activity using response surface methodology (RSM). Optimum SFE pressure, temperature, static time, and dynamic time levels are determined as 350 bar, 50 °C, 20 min, and 90 min, respectively. Oil yield and physicochemical quality properties of conventional solvent extract and SFE samples are determined and compared. Consequently, samples obtained via SFE and solvent extraction have similar quality properties. Distinctly, SFE allows an extraction with 5.6% higher total phenolic compound (TPC) and 33% higher antioxidant activity than solvent extraction. Practical Applications: In the study, the extraction of purslane oil using supercritical fluid extraction is optimized with different approaches. At optimum conditions, purslane oil is extracted and all physicochemical properties and the process efficiency (yield) are compared with the solvent-extracted samples. The results of this study make supercritical fluid extraction of purslane seed oil possible since all optimum operating conditions of a pilot-sized extractor are reported in the study. It is believed that the results provide a good starting point for industrial operations. Moreover, researchers also believe that research studies unveiling the new potential oil-bearing seeds are important to overcome the vegetable oil shortage that emerged this year.  相似文献   

3.
超临界CO_2萃取结合柱色谱分离萝芙木生物碱   总被引:5,自引:1,他引:5  
周雪晴  冯玉红  张冲  林强 《精细化工》2007,24(2):154-155,161
用超临界CO2萃取技术,设计了4因素3水平正交实验,研究从海南催吐萝芙木中提取利血平生物碱的最佳工艺。最佳提取条件为:萃取压力35 MPa,萃取温度60℃,夹带剂为100 g样品用25 mL乙醇,萃取时间2 h。用高效液相色谱法对萃取产物中的利血平含量进行了测定。将萃取所得产物用硅胶柱色谱进一步分离提纯,得到了质量分数为99.8%的利血平针状结晶。  相似文献   

4.
《分离科学与技术》2012,47(16):2501-2509
Supercritical fluid extraction (SFE) was used to extract three isoflavonoids including irigenin, irisfloretin and dichtomitin from Belamcanda chinensis (L.) DC. The parameters including pressure, temperature, sample particle size, and flow rate of CO2 were optimized with an orthogonal test. Under the optimized conditions of 15 MPa, 55°C, a sample particle size of 20–40 mesh and CO2 flow rate of 40 L h?1. The process was then scaled up by 10 times using a preparative SFE system. The yield of the crude extract from SFE was 4.1%, which contained irigenin, irisfloretin, and dichtomitin 0.71%, 0.49%, and 0.05%, respectively. To compare the extraction methods, Soxhlet Extraction (SE) was performed. The results indicated that SFE was better than SE. Irigenin, irisfloretin, and dichtomitin in the SFE extract were then separated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of petroleum ether–ethyl acetate–methanol–water (2:4:3:3, v/v). From 5.0 g of dry crude extract, 27.8 mg irigenin, 16.4 mg irisfloretin, and 2.1 mg dichtomitin were obtained at purities of 97.1%, 96.4%, and 98.0%, respectively, as determined by HPLC-PDA. These results well indicate that SFE and HSCCC are very powerful techniques for the extraction and purification of irigenin, irisfloretin, and dichtomitin from B. chinensis.  相似文献   

5.
《分离科学与技术》2012,47(10):2327-2345
Abstract

A custom‐built, solvent recirculating, supercritical fluid extraction (SFE) apparatus was used to study the extraction of hydrocarbons from a crude oil tank bottom sludge (COTBS) with supercritical ethane. The SFE experiments were carried out varying the pressure (10 MPa and 17.20 MPa) and temperature (35°C and 65°C). The yield of the extracted hydrocarbon fraction increased with increase in extraction pressure at constant temperature, and decreased with increase in extraction temperature at constant pressure. The maximum extraction yield was obtained at the pressure and temperature conditions that lead to the highest solvent density. The extracted hydrocarbon fraction was a significantly upgraded liquid relative to the original untreated COTBS.  相似文献   

6.
For arbitrarily chosen thirty types of natural resources which have been widely used in oriental traditional herb medicine, supercritical CO2 extraction (SFE) and organic liquid solvent extraction (LSE) withn-hexane, chloroform and methanol were carried out to extract pharmaceutical substances. To evaluate relative advantages and shortcomings between the SFE and LSE, five types of bioactivity assays as well as gas- and thin layer-chromatographic analysis were performed for all the extracts obtained by the two extraction methods. Types of bioassays performed included cytotoxicity, bleb forming, DNA binding, oxygen free radical scavenger and Xanthine oxidase inhibitor tests. To evaluate economic viability of the SFE over the traditional LSE, extractability of prodrug substances was evaluated as the functions of extraction temperature and pressure. SFE was proven to be a feasible alternative over LSE. Also, the optimum SFE conditions which provided maximum extraction and cytotoxicity for each selected sample were presented.  相似文献   

7.
《分离科学与技术》2012,47(11):1829-1837
The separation processes of the phenolic compounds from solid plant matrixes are of great importance. In the scope of developing more efficient methods to separate olive leaf extract, dried and ground olive tree leaves from Aegean region of Turkey were extracted by means of Soxhlet and supercritical fluid extraction (SFE) methods. In the Soxhlet method, different types of solvents (hexane, water, ethanol, methanol, and methanol/hexane (3:2, v/v) mixture) were used to determine the effect of the solvent type on the extraction performance. In the SFE method, the effect of pressure (100–300 bar), temperature (50 and 100°C), and type of co-solvent on the amount of both extract and oleuropein were investigated. Ethanol, methanol and water were selected as co-solvent in 20% (v/v) amount. Quantitative analysis was performed by using a liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) technique. The results of SFE were compared with those obtained by the Soxhlet method. Whereas the highest oleuropein yield was achieved via the Soxhlet method through methanol with the value of 37.84 mg/g dried leaf, the best oleuropein yield was achieved with the value of 14.26 mg/g dried leaf by using CO2 modified by methanol at 300 bar and 100°C in the SFE method.  相似文献   

8.
《分离科学与技术》2012,47(16):2391-2398
The present study focuses on developing methods for olive leaf extraction and deals with obtaining extract, rich in oleuropein, which is the most abundant phenolic compound in olive leaves. Supercritical fluid extraction (SFE) was applied to the dried and ground olive leaves by using CO2 as supercritical (SC) fluid in the presence of water and ethanol as co-solvent. The influences of operating parameters by means of co-solvent content (0-1 mL/min), temperature (50 and 100°C) and pressure (100-300 bar) on both extract and oleuropein yields were investigated. Quantitative analysis was performed by using a liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) technique. The experimental results obtained by using SC-CO2 alone were not satisfactory, and it was seen that addition of a polar modifier is necessary in order to improve yield and selectivity of the process. It was observed that CO2 modified by water and ethanol showed nearly the same extract performance, where CO2 modified by water is better for high oleuropein yield.  相似文献   

9.
《分离科学与技术》2012,47(9):2004-2021
Abstract

10-Deacetylbaccatin III was extracted from the ground needles of Taxus baccata L. growing in Turkey using sub- and supercritical carbon dioxide with and without co-solvents by using two different methods (as an entrainer and modifier) and compared to Soxhlet extraction. SFE applications were carried out in the pressure range between 10 to 40 MPa and temperature ranges between 35 to 45°C. Recovery of the target compound increased with increasing temperature and pressure. The highest quantity of 10-deacetylbaccatin III obtained from needles of Taxus baccata L. was about 718 mg/kg when 200 µL of methanol was used as an entrainer at 45°C.  相似文献   

10.
Supercritical Fluid Extraction, Microwave Assisted Extraction and Soxhlet Extraction for the Analysis of PCB's in Soil and Sewage Sludge The supercritical fluid extraction (SFE) was applied on the analysis of PCB's in soil and sewage sludge. Some questions concerning the performance of SFE were studied. With spiked samples and the modifier toluene put directly onto the sample the effect of a static extraction before the dynamic extraction step is described. It was found that matrices with a high content of total organic carbon show matrix effects in SFE, which was identified by calibration of the whole analytical process and eliminated by repeating the extraction. Two real samples were used to compare the SFE with soxhlet extraction and organic solvent extraction by means of microwave energy. The extracts were cleaned by column chromatography on aluminium oxide and silica gel modified with silver nitrate and afterwards analysed by GC-ECD and GC-MS (SIM mode). Soxhlet and SFE gave comparable results. The best extraction results were achieved by microwave assisted extraction with a solvent mixture of hexane/acetone 3:1.  相似文献   

11.
超临界CO_2萃取大豆磷脂的影响因素研究   总被引:2,自引:0,他引:2  
吕维忠  钟振声  黄少烈 《精细化工》2001,18(3):151-152,169
应用超临界CO2 萃取技术从大豆粗磷脂中提纯得到了质量分数为 98%的大豆磷脂。研究了萃取压力、萃取温度、萃取时间对萃取率的影响 ,3个影响因素的影响顺序为 :萃取温度 >萃取时间 >萃取压力。优化工艺条件是 :萃取压力 2 0MPa ,萃取温度 5 0℃ ,萃取时间 5h。  相似文献   

12.
A simple two-step process was developed to extract and purify medium chain-length polyhydroxyalkanoates (MCL-PHA) from bacterial cells (Pseudomonas resinovorans) grown on lard and tallow. The process consists of supercritical fluid extraction (SFE) of the lyophilized cells with carbon dioxide to remove lipid impurities, followed by chloroform extraction of the cells to recover the MCL-PHA. SFE conditions were varied as to temperature (40–100°C), pressure (2000–9000 psi), and carbon dioxide flow rate (0.5–1.5 L/min, expanded gas). Lipid material, usually 2–4%, but in some cases as high as 11%, was extracted from the dried cells by SFE. A pressure range (5000–9000 psi, increased stepwise), a temperature of 60°C, and a carbon dioxide flow of 1.5 L/min were routinely used to extract the bacterial cells (4–5 g) after 3 h. Higher flow rates could shorten the extraction time even more. SFE did not extract MCL-PHA from the cells. Yield of MCL-PHA after chloroform extraction at room temperature was a maximum of 42.4% based on dry cell weight. The results show that the two-step process saves time, uses much less organic solvent, and produces a purer MCL-PHA biopolymer than previous extraction and purification methods. A more environmentally friendly clean-up procedure based on SFE and organic solvent recovery was developed to remove contaminating lipid materials from the fermentation biomass, allowing for the recovery of higher purity MCL-PHA that are suitable for more demanding applications.  相似文献   

13.
《分离科学与技术》2012,47(4):569-579
The extract of lemon verbena ( Aloysia triphylla ) was obtained by supercritical fluid extraction (SFE) using laboratory and pilot scale equipments. The scale-up criterion selected (maintaining solvent to feed ratio constant) was successfully used for a 14-fold scale-up. The extract obtained in pilot scale was separated in three fractions, which were characterized as for their phytochemical profile, total flavonoids content, and antioxidant activity. The extracts obtained by SFE were compared to classical Soxhlet extraction method. Maximum yield obtained for SFE was 1.8%, and for Soxhlet, 7.1%. The chemical composition revealed different phytochemical profiles for SFE and Soxhlet extracts; the last ones presented more flavonoids, while SFE extracts were more concentrated in volatile compounds. The major compounds identified in the volatile fraction of the extracts were spathulenol, phytol and octadecatrienal. Some extracts presented pro-oxidant activity and others presented antioxidant activity. The SFE process was shown to be economically feasible for obtaining lemon verbena extracts; the minimum manufacturing cost (COM) obtained was US$ 1070.00/kg, with a payback time of 2 years.  相似文献   

14.
《分离科学与技术》2012,47(17):2695-2703
ABSTRACT

Peanut skin is a waste by-product from peanut industries. It is rich in antioxidants and bioactive compounds. Therefore, the objective of this study was to empirically model and optimize supercritical CO2 extraction of oil from peanut skin. The extraction conditions were pressure (100, 200 and 300 bar), temperature (313, 328 and 343 K) and rate of modifier ethanol (0.075, 0.15 and 0.225 mL/min). The extraction process was subsequently examined using modified Brunner and Esquivel models. The optimum conditions for extraction peanut skin oil were 279 bar, 70°C and rate of modifier of 7.5% with a maximum yield of peanut skin oil of 0.83 g and initial slope of 0.568 g/min.  相似文献   

15.
罗群  陈洪伟  梁志辉  范洪波 《广东化工》2011,38(3):118-119,142
电子电器产品中含溴阻燃剂的萃取方法有索氏萃取、自动索氏萃取、超声波萃取、超临器萃取、微波辅助萃取和快速溶剂萃取等.文章通过对比索氏萃取、微波辅助萃取和快速溶剂萃取并结合高效液相色谱法测定电子塑料产品中的含溴阻燃剂,探讨合适的萃取方法,实验结果表明,索氏萃取效果最好,回率91.8%~98.4%,RSD%=5,满足检测要求...  相似文献   

16.
《分离科学与技术》2012,47(6):972-977
Supercritical carbon dioxide modified with acetonitrile and water for the extraction of indirubin and tryptanthrin from Folium Isatidis and the collection of these two bioactive ingredients by a spray mode are presented in this study. Two pumps, one for the addition of the modifier and the other for the transportation of CO2, were used for supercritical fluid extraction (SFE). This is a fast and environmentally-friendly approach for the production of herbal medicine. Compared to conventional solvent extraction, the yield of bioactive indirubin and tryptanthrin by this SFE process was approximately the same, but with a shorter process time and better protection of the environment.  相似文献   

17.
Rape bee pollen lipids obtained by petrol ether extraction (PEE) or supercritical fluid (carbon dioxide) extraction (SFE) were compared with regard to their free fatty acid (FFA) components. Optimal SFE conditions were selected by carrying out the Taguchi method with an OA9 (33) matrix design, and are as follows: extraction pressure at 35 MPa, temperature at 45 °C, and dynamic extraction time at 90 min. The lipid yield based on PEE was 7.42 wt‐% and the extracts of the desired analytes based on SFE varied in the range of 3.23–5.58 wt‐% under different conditions. With the optimized procedure, the lipid yield was 6.09 wt‐%. The FFA in the lipids were separated with a pre‐column derivation method and 1‐[2‐(p‐toluenesulfonate) ethyl]‐2‐phenylimidazole [4,5‐f]9,10‐phenanthrene as labeling regent, followed by high‐pressure liquid chromatography (HPLC) with fluorescence detection. HPLC analysis shows that the lipids contain abundant unsaturated fatty acids (UFA) in high to low concentrations as follows: linolenic acid (18:3), oleic acid (18:1), linoleic acid (18:2), nervonic acid (24:1), and lignoceric acid (20:4). The UFA contents in the SFE extracts were higher than those after PEE. The results indicated that SFE under suitable conditions is more selective than conventional PEE with regard to lipid extraction and preservation of their quality.  相似文献   

18.
Supercritical CO2 extraction with a static modifier was applied to extract chlorophyll a from Spirulina platensis. The effects of the process were investigated by single‐factor and response surface analysis experiments. The optimal process parameters for supercritical CO2 extraction were determined to be: ethanol/water as the modifier, 40 vol.‐% water content in the modifier, 21.2 mL modifier volume, 1 h static soaking time, 2 h dynamic extraction time, 48.7 MPa extraction pressure, 326.4 K extraction temperature, and 10 g min–1 CO2 flow rate. The optimized chlorophyll a extraction yield was 6.84 mg g–1. A comparison of the experimental results suggested that the yield of chlorophyll a by supercritical CO2 extraction with modifier was higher than that obtained by conventional solvent extraction.  相似文献   

19.
The aim of the present study was to use supercritical technology to recover linseed oil (Linum usitatissimum L.) using carbon dioxide (alone or modified with ethanol as solvent) to determine the influence of the technique on the chemical composition of the oil obtained, model the kinetic curves of extraction, and estimate the manufacturing cost of the process. The experiments were conducted at 323 K, pressure of 25 MPa, constant solvent flow of 1.7 × 10?5 kg/s, and extraction time of 5 h. The highest yield was obtained with the addition of cosolvent (28.8%). The SFE process of linseed oil manufacture proved to be economically viable, resulting in a product with a specific cost of 13.21 US$/kgoil. As to oil composition, the main fatty acids detected were linolenic and oleic acid.  相似文献   

20.
This study investigated the supercritical fluid extraction (SFE) of geranium essential oil from geranium (Pelargonium graveolens) using supercritical carbon dioxide solvent. The extraction yield was measured as a function of pressure, temperature and carbon dioxide flow rate. At low pressure (10 MPa) and high temperature (343 K), waxes were co‐extracted with the essential oil, resulting in artificially elevated essential oil extraction yields as no method was available with the SFE apparatus used to separate co‐extracted waxes and oil. At high pressure (30 MPa) and low temperature (313 K), the amount of wax co‐extracted decreased. Under these ‘optimum’ conditions, the extraction yield increased with decrease in flow rate giving a maximum extraction yield of 2.53%. All samples were analyzed by gas chromatography–mass spectrometry and the effect of pressure and extraction time on oil composition was studied. The percentage compositions of terpene hydrocarbons, terpenols, geraniol and geranyl esters were significantly affected by pressure and extraction time. The oil samples obtained by SFE were also compared with commercially obtained steam distilled samples. All major components of the commercially obtained oils were present in the SFE‐obtained oils; however, the percentage composition of the major components differed greatly between steam distilled and SFE oils. Copyright © 2005 Society of Chemical Industry  相似文献   

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