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1.
李斌  韩凌  彭华松  唐涌濂 《化学世界》2005,46(4):213-215,222
考察了萃取压力、萃取温度、工作流量和时间等因素对超临界CO2萃取石菖蒲挥发油的影响.分别以萃取得到的挥发油得率、挥发油中α-细辛醚含量及α-细辛醚萃取率为指标,通过单因素试验获得石菖蒲挥发油超临界萃取的最佳工艺条件以及最佳萃取结果,即得油率4.86%,α-细辛醚含量3.17%,α-细辛醚萃取率1.26×10-3,同时也与水蒸气蒸馏方法进行了比较,结果表明超临界CO2萃取石菖蒲挥发油中α-细辛醚的含量要稍低于水蒸气蒸馏法,但其得油率及α-细辛醚的萃取率要明显优于传统的水蒸气蒸馏法.  相似文献   

2.
超临界CO2萃取的研究进展   总被引:2,自引:0,他引:2  
超临界CO2流体萃取技术是近年来兴起的一项具有精馏和萃取两过程的高新物质分离精制技术,文章主要通过对各类超临界CO2流体萃取实验的文献报道和实验操作进行分析,对超临界CO2流体革取技术的原理、特点和超临界CO2流体萃取的主要影响因素及其优化方法和经验模型进行了综述。  相似文献   

3.
超临界CO2流体萃取莪术挥发油的工艺研究   总被引:3,自引:0,他引:3  
利用超临界CO2流体萃取技术,以榄香烯为目标物,研究了萃取压力、温度、时间、原料粒度和CO2流量对莪术挥发油萃取率的影响,建立了获得莪术挥发油的最佳工艺条件。实验结果表明,莪术粉粒度40目,萃取压力18MPa,温度50℃,萃取时间120min,流量20—30kg/h条件下,挥发油中榄香烯含量最高,相对含量为2.8%,为以后精馏研究奠定了基础。  相似文献   

4.
超临界CO2和微波辅助萃取辽细辛挥发油   总被引:3,自引:0,他引:3  
通过超临界CO2萃取辽细辛挥发油均匀设计实验和微波诱导萃取的正交实验比较,考察了影响提取的主要因素,得到了最佳萃取工艺. 超临界CO2萃取最佳工艺条件为:压力16 MPa,温度32oC,CO2流量20 kg/h和时间80 min,得率为3.78%;微波萃取最佳工艺条件为:辐射功率720 W,辐射时间50 s,溶剂用量300 ml,洗涤溶剂用量30 ml,得率为5.46%. 水蒸馏法提取率为1.62%. 结果表明,超临界CO2和水蒸馏法萃取辽细辛挥发油品质最好;微波萃取收率最高,但品质较差.  相似文献   

5.
采用超临界CO2萃取牛至药材中的挥发油,以挥发油产品中两种主要有效成分的质量总和为考察指标,以萃取压力、萃取温度、萃取时间、夹带剂浓度及夹带剂流量为考察因素进行正交实验,优选最佳的萃取工艺条件。最佳的萃取工艺条件为:萃取压力为25 MPa、萃取温度为55℃、萃取时间为2.5 h、75%乙醇为夹带剂、夹带剂流量为0.02mL/min、CO2流量为1 L/min,在此实验条件下,产品中两种主要有效成分的质量总和平均为0.141 24 g。优选得到的萃取工艺可靠、简便易行、稳定性好。  相似文献   

6.
7.
青皮挥发油超临界 CO2 萃取的GC-MS测定   总被引:1,自引:0,他引:1  
采用超临界CO2流体萃取中药青皮中的挥发油,通过气相色谱-质谱联用技术对其化学成分进行分离鉴定,并以面积归一化法测定了各组分的相对含量。结果表明,青皮挥发油的主要化学成分为d-柠檬烯、正二十烷、(Z,Z,Z)-9,12,15-十八碳三烯酸-2,3-二羟丙基酯、(Z)-9-十八碳烯酸甲酯、γ-谷甾醇、1-甲基-4-(1-甲基乙烯基)-1,2-环己二醇、棕榈酸甲酯、2-甲基-1-鲸蜡醇等,为青皮的进一步研究利用提供了参考。  相似文献   

8.
采用超临界CO2流体萃取中药青皮中的挥发油,通过气相色谱-质谱联用技术对其化学成分进行分离鉴定,并以面积归一化法测定了各组分的相对含量。结果表明,青皮挥发油的主要化学成分为d-柠檬烯、正二十烷、(Z,Z,Z)-9,12,15-十八碳三烯酸-2,3-二羟丙基酯、(Z)-9-十八碳烯酸甲酯、γ-谷甾醇、1-甲基-4-(1-甲基乙烯基)-1,2-环已二醇、棕榈酸甲酯、2-甲基-1-鲸蜡醇等,为青皮的进一步研究利用提供了参考。  相似文献   

9.
孙凯  崔鹏 《安徽化工》2012,38(2):34-36
以鱼腥草为原料,进行超临界CO2萃取分离鱼腥草挥发油的工艺研究.重点考查了温度、压力、时间对产品得率的影响.正交实验结果表明:影响萃取的主次因素为B(压力)>A(温度)>C(时间);较佳工艺参数为萃取温度50℃,压力22MPa,时间90min,且水为夹带剂时,鱼腥草挥发油的总得率高达1.95%,其中鱼腥草素的得率达0.05%.  相似文献   

10.
超临界CO2萃取的研究进展   总被引:3,自引:0,他引:3  
通过对各类超临界CO2流体萃取实验的文献报道和实验操作进行分析,对超临界CO2流体萃取技术的原理、特点和超临界CO2流体萃取的主要影响因素及其优化方法和经验模型进行了综述.  相似文献   

11.
Liquid drilling fluid is often called drilling mud is heavy, viscous fluid mixtures use to carry rock cuttings to the surface and lubricate and cool the drill bit. During carrying cuttings they contaminated which not only reduce their functionality but also make them a hazardous and dangerous wastes which cannot be discharged anywhere without treatment. Due to this fact, in the present study, supercritical extraction process was used to remove contaminants from the drilling mud. Regarding this, effect of different parameters including extraction temperature (313–338 K) and pressure (100–200 bar), flow rate of CO2 (0.05–0.36 cm3/s) and static time (20–130 min) on the removal of contaminations from drilling mud was examined using the design of experiment of changing one factor at a time. The obtained results revealed that the optimum operational conditions that lead to the highest removal degree of contaminations are temperature and pressure of 333 K and 180 bar, respectively, flow rate of lower than 0.1 cm3/s and the static time of 110 min. In addition, to examine the effect of the supercritical extraction on the crystalline structure modification and removal contaminations X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were performed which confirmed the successful removal of contaminations from the drilling mud without significant crystalline modification.  相似文献   

12.
采用二氧化碳超临界萃取乙基香兰素粗品,研究萃取压力、萃取温度、萃取时间、流体流量等工艺条件对萃取效率和产品质量的影响.得出最佳工艺条件,采用萃取压力25~30 MPa,萃取温度55~60℃,流体流量5 L/h,萃取5~6 h,萃取效率可以达到95%,可以得到质量分数大于95%的乙基香兰素产品.  相似文献   

13.
超临界CO_2萃取大豆油的实验研究   总被引:11,自引:0,他引:11  
采用超临界CO2 萃取技术进行了大豆油的萃取实验。在压力为 2 0~ 30MPa、温度为 30 8~ 32 3K的范围内 ,考察了萃取压力、萃取温度、流体流量和物料预处理方式等条件对出油率的影响。在本文实验范围内 ,大豆油的最佳萃取工艺条件为 :压力 30MPa ,温度 313K ,物料状态为约 0 .4mm厚的大豆片。流体流量只影响萃取速率 ,而不影响最终的出油率  相似文献   

14.
Supercritical carbon dioxide extraction to purify samples of model hydrocarbons (tetralin, decalin, and tetradecane) containing various aromatic sulfur compounds (benzothiophene, dibenzothiophene, and 4,6-dimethydibenzothiophene) was studied. The influence of extraction temperature and pressure was investigated for the extraction from a tetralin-dibenzothiophene system in the range of 293-353 K and 8-15 MPa, and it was found that the amount of tetralin extracted increased with an increase in carbon dioxide density, while the separation factor decreased with an increase in carbon dioxide density. High recovery and high separation factor values for the tetralin-dibenzothiophene system were obtained under 10 MPa at 313 K. Higher separation factor was obtained for tetralin than decalin and tetradecane, containing 4,6-dimethyldibenzothiophene than that containing dibenzothiophene.  相似文献   

15.
采用二氧化碳超临界萃取酸性水溶液中3-甲氧基-4-羟基苯甲醛(香兰素),含有3-甲氧基-4-羟基苯甲醛的水溶液与超临界二氧化碳流体在萃取柱中连续逆流混合,研究得出最佳工艺条件:压力(22~26)MPa;萃取温度55~60℃,超临界流体与原料液体质量比5.5:1,此条件下,萃取效率95%以上,可以得到质量分教大于90%的产品.  相似文献   

16.
Reactive extraction using supercritical carbon dioxide (scCO2) and tri-n-octylamine (TOA) was evaluated as a separation method of succinic acid from an aqueous solution. The reactive extraction of succinic acid was performed at varying initial acid concentrations in aqueous solution (0.07–0.45 mol?dm?3), temperature (35–65°C) and pressure (8–16 MPa). The succinic acid separation was conducted in both batch mode and semi-continuous mode. The highest reactive extraction efficiency of approx. 62% was obtained for the process conducted in semi-continuous mode at 35°C and 16 MPa for the initial acid concentrations in aqueous phase of 0.39 mol?dm?3.  相似文献   

17.
超临界CO2萃取的研究与应用   总被引:4,自引:0,他引:4  
沈国良 《化工时刊》2001,15(12):10-13
介绍了超临界流体的特性及其萃取的基本原则,讨论了超临界流体萃取技术的优点,评述了超临界CO2的特点,概述了国内外超临界CO2萃取技术在医药,食品,香料,石油化工以及环境保护等领域的开发及应用。  相似文献   

18.
Supercritical carbon dioxide was used for partially selective extraction of triacetin from a mixture of triacetin, diacetin, and monoacetin with a molar ratio of 1:2:1. The extraction was carried out in two stages. In the first stage, a central composite design was used to optimize the four variables of pressure, temperature, liquid CO2 flow rate, and extraction time at three levels using a semi-continuous, supercritical carbon dioxide extraction setup. The composition of the extract under the predicted optimum conditions (i.e., 109 bar, 56 °C, 0.86 mL min−1, and 61 min) was about 69% triacetin accompanied by only 30% diacetin and no detectable monoacetin. In the second stage, the effect of the two factors, pressure (100, 109, and 140 bar) and liquid CO2 flow rates of 0.86 and 1.5 mL min−1 measured at average laboratory temperature (27 °C) and pressure (0.89 bar), were studied using a continuous, supercritical carbon dioxide fractionation setup equipped with a glass-bead packed column kept under a thermal gradient of 56-70 °C. The experimental design was organized as a 3 × 2 general factorial design. Under the best conditions (i.e., 140 bar and 1.5 mL min−1), the extraction yield of triacetin and diacetin were 41.8 and 3.0%, respectively, without any detectable monoacetin as verified by GC-FID.  相似文献   

19.
The purpose of this study was to investigate obtaining of caffeine from tea plant wastes by supercritical carbon dioxide extraction. Experiments were carried out with tea stalk and fiber wastes of Turkish tea plants that has no economical value. Stalk and fiber wastes were supplied from tea factories. These wastes were ground, sieved and dried at 105 °C temperature in an oven. Parameters affecting caffeine leaching from tea wastes were determined to be, extraction time, extraction temperature, carbon dioxide flow rate, process pressure and particle size. The maximum yield of caffeine from tea stalk wastes and fiber wastes were 14.9 mg/g tea stalk and 19.2 mg/g tea fiber, respectively. The yield increase had been recorded as 61.9% and 65.5%, respectively, in comparison with the chloroform extraction of tea stalk and fiber wastes.  相似文献   

20.
This study presents the effect of ethanol content on supercritical carbon dioxide extraction of caffeine from tea plant wastes. Tea stalk and fiber wastes of Turkish tea plants that have no economical value were evaluated as raw material throughout the caffeine extraction experiments. These wastes were supplied from tea factory marked “Çaykur” in the east blacksea region. They were separately ground, sieved and dried at 105 °C temperature in an oven. Parameters affecting caffeine leaching from tea wastes were determined to be, ethanol flow rate, extraction time, extraction temperature, carbon dioxide flow rate, process pressure and particle size. The maximum yield of caffeine from tea stalk wastes and fiber wastes were 14.95 mg/g tea stalk and 18.92 mg/g tea fiber, respectively. When the supercritical extraction conditions used of ethanol as cosolvent have been compared with the conditions of used only carbon dioxide, approximately the same yield has been reached at 2 h extraction period instead of 7 h. Beside of saving of the time and the amount of carbon dioxide, the supercritical extraction yield with cosolvent increase had been recorded as 62.5% and 63.1%, respectively, in comparison with the chloroform extraction as conventional method of tea stalk and fiber wastes.  相似文献   

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