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1.
王莉明  文若颖 《辽宁化工》2002,31(7):315-317
根据超临界流体的特点,评述了毛细管超临界流体色谱在仪器、应用方面的最新进展及其发展前景。  相似文献   

2.
新型分离技术--工业高效制备色谱   总被引:3,自引:0,他引:3  
王华  韩金玉  常贺英 《现代化工》2004,24(10):63-65
工业高效制备色谱技术是一种新型、高效、节能的分离技术.介绍了模拟移动床色谱、VariCol色谱和超临界流体色谱3种主要的工业高效制备色谱的原理和应用,并扼要介绍了工业高效制备色谱分离过程的模拟和优化方法.  相似文献   

3.
综述了超临界流体色谱应用于手性药物的进展。超临界流体色谱正在从单纯地对对映体进行鉴定的分析规模,转向能生产几毫克到几百克物质的半制备或制备规模。快速筛选手性同定相和调节剂是成功应用超临界流体色谱于制备过程的关键。  相似文献   

4.
用于制备规模的超临界流体色谱分离对映体受到青睐   总被引:2,自引:0,他引:2  
综述了超临界流体色谱应用于手性药物的进展。超临界流体色谱正在从单纯地对对映体进行鉴定的分析规模,转向能生产几毫克到几百克物质的半制备或制备规模。快速筛选手性固定相和调节剂是成功应用超临界流体色谱于制备过程的关键。  相似文献   

5.
综述了超临界流体中的化学反应、超临界流体萃取、超临界流体色谱在废弃物处理、清洁生产和环境分析等方面的应用。  相似文献   

6.
超临界流体技术在环境保护中的应用研究   总被引:14,自引:0,他引:14  
综述了超临界流体技术在环境保护各领域的应用。介绍了国内外超临界流体技术 (超临界水反应、超临界萃取以及超临界色谱 )处理环境污染物的实例  相似文献   

7.
以二氧化碳为流动相,ODS柱为固定相,测定了二十碳五烯酸乙酯(EPA-EE)和二十二碳六烯酸乙酯(DHA-EE)的超临界流体色谱容量因子。从宏观热力学出发,研究了溶质的超临界流体色谱容量因子及其在超临界二氧化碳中溶解度的关系,并用实验数据对该热力学关系作了验证。  相似文献   

8.
超临界流体色谱在手性分离中的应用   总被引:4,自引:0,他引:4  
郭亚东 《化学试剂》2000,22(6):347-351
综述了超临界流体色谱在手性分离中的应用,讨论了3类手性固定相、二元流动相、三元流动相和温度对分离的影响。对超临界流体色谱的手性分离中的应用作了展望。  相似文献   

9.
超临界流体在环境保护中的应用和展望   总被引:1,自引:0,他引:1  
王代芝 《辽宁化工》2007,36(6):392-394,397
超临界流体技术广泛应用于化工、医药、生物、食品、陶瓷等领域。将超临界流体技术用于环境保护则是一个新的研究方向,由于该技术对废物处理具有经济、快速、高效等特点,近几年来发展异常迅速。综述了超临界流体的特性以及超临界流体技术(超临界萃取、超临界色谱和超临界水氧化)在环境保护方面的应用现状。  相似文献   

10.
采用超临界CO2流体萃取法(SFE)从小茴香中提取挥发油。用气相色谱-质谱联用技术对化学成分进行分析,共鉴定了50种成分,占挥发油总成分的81%以上。超临界CO2流体萃取法提取的挥发油能更真实、全面地反映小茴香中的化学成分。  相似文献   

11.
A COSMO base activity coefficient model was newly developed to predict the solubilities of solid solutes in supercritical carbon dioxide. This activity coefficient model describes that the system is composed of the surface segments on the solvent molecule and vacancy unlike the conventional model based on COSMO method. The density change of supercritical fluid can be represented by the change of the surface area of the vacancy. This prediction model is referred to “COSMO-vac (vacancy)” model. The solubilities of 16 pharmaceuticals in supercritical carbon dioxide were predicted by COSMO-vac model. The averaged deviations between the logarithmic experimental and predicted results are smaller than unity. Furthermore, the predicted results for the solutes composed of only C, H and O atoms are better than those for the solutes including the other atoms. The percentage of the predicted results within the order of the experimental data at the pressure over 15 MPa is higher than that at the pressures below 15 MPa.  相似文献   

12.
从20世纪70年代末兴起超临界流体技术以来,人们已经对超临界萃取进行了大量的研究.近几年来,研究的热点转向超临界的粒子制备、物质的超临界处理、超临界聚合和聚合物的超临界分离.而在所有的超临界流体技术研究中,一个很重要的基础问题就是需要了解和预测超临界流体的  相似文献   

13.
Supercritical fluid extraction of chamomile using carbon dioxide was investigated in the current study. A model that accounts for both particle and fluid phase was presented for the supercritical extraction. The distribution coefficient of chamomile extract, between solid and solvent has been determined using genetic algorithm method. The model was solved numerically and was successfully validated with experimental data. The model was found to give superior results when compared to experimental data. The effect of particle diameter on extraction yield was investigated using the proposed model. Using genetic algorithm optimization technique 313.15 K and 20 MPa were found as the optimum temperature and pressure, respectively.  相似文献   

14.
在半连续式实验设备中分别测定了苯甲醇-2-苯乙醇和苯甲酸酯-苯甲醇的等摩尔混合物与超临界CO2三元系相平衡数据。实验温度分别为308.2K和318.2K,压力范围为8~20MPa。实验结果表明:对第一个三元系,两种液体在超临界CO2中的溶解度与CO2在液相中溶解行为密切相关;对第二个三元系,较高压力下,超临界流体相中苯甲酸甲酯浓度突然增大,而苯甲醇浓度变化不明显。通过引入考虑分子体积差别的二元作用参数,用Peng-Robinson方程对气液平衡数据进行了关联。  相似文献   

15.
药物微粒化可改善其溶出度,提高生物利用度。为应用超临界流体技术制备阿昔洛韦(Acyclovir)微粒,用静态法测定了在313.15~413.15K,10.0~30.0MPa下阿昔洛韦在超临界CO2中的溶解度。阿昔洛韦的溶解度较小,在10^-5~10^-7(摩尔分率)之间,溶解度随着温度和压力的升高而增大,不存在文献报道的反向区。采用P-R方程对溶解度数据进行关联,平均相对误差为10.0%。  相似文献   

16.
超临界流体萃取沙棘油实验研究   总被引:11,自引:0,他引:11  
建立了一套萃取实验装置 ,对超临界CO2 流体萃取沙棘油进行了实验研究。压力 15— 30MPa,温度 30— 5 0℃。分别考察了萃取压力、萃取温度、颗粒度、物料填充量以及萃取时间等条件对萃取率的影响 ,并就工艺参数对萃取率的影响机理和原因进行了分析与讨论。结果表明 :当压力为 2 5MPa、温度为 40℃时可获得较高的萃取率。流量为 0 .2m3 /h时 ,萃取时间为 4— 5h。化学成分分析结果证明 :沙棘油中饱和脂肪酸含量占 12 .3%,不饱和脂肪酸含量占 87.7%。  相似文献   

17.
The separation method using chiral stationary phase (CSP) for the preparation of enantioselective compound was widely used. In this work, supercritical fluid chromatography(SFC) was proposed to resolve the chiral mixtures. To determine the optimum operating conditions for the chiral separation of the racemic ibuprofen, the retention factors and resolutions with the change in pressure, temperature and the content of IPA (%, by volume) in supercritical CO2 were investigated. Experiments showed that the retention factor decreased with the increase of pressure and decrease in temperature. The retention factor was also influenced by the content of IPA in mobile phase, as the content of IPA in the supercritical fluid increased, the retention factor decreased. The resolution of the enantiomers became worse with the increase of IPA in the supercritical fluid. Through optimizing the experimental conditions, a SFC procedure with 13MPa, 311.15K and 4% IPA in CO2 was obtained. The peak shape of the enantiomers was symmetric with supercritical fluid chromatography when compared to the asymmetric peak shape obtained by the conventional liquid chromatography. This work demonstrated that the developed supercritical fluid chromatography procedure was suitable for the chiral separation of ibuprofen enantiomers.  相似文献   

18.
In the present study, a mathematical modeling for extraction of oil from clove buds using supercritical carbon dioxide was performed. Mass transfer is based on local equilibrium between solvent and solid. The model was solved numerically, and model estimation was validated using experimental data. For optimization, the clove oil equilibrium constant between solid and supercritical phase was determined by a theoretical method using fugacity concept, consequently the genetic algorithm for obtaining optimal operational conditions was used. The optimal conditions which obtained the highest amount of clove oil were pressure of 10 MPa and temperature of 304.2 K.  相似文献   

19.
本文利用超临界CO2萃取沙棘油,建立了一套实验流程,分别考察了萃取压力、萃取温度以及颗粒大小对萃取率的影响。同时根据萃取器单元的质量守恒建立了微分方程,并对一定萃取条件下的实验结果进行数值模拟。结果表明, 本文所建立的数值模型能较好地描述实际萃取行为。  相似文献   

20.
A computational fluid dynamics model of extraction of a solute (caffeine) from a porous solid matrix (coffee beans) using a supercritical solvent (carbon dioxide) is developed. Supercritical fluid extraction of a solute from a solid matrix is a slow process even when solute free solvent is circulated. The use of acoustic waves represents a potential efficient way of enhancing mass transfer processes. The effect of acoustically excited flows on supercritical fluid extraction from a porous solid matrix is investigated. The mathematical model considers diffusion-controlled regime in the porous solid matrix and convective-diffusive transport in the bulk fluid. Henry's law is used to describe the equilibrium states of the solid and the fluid phases. Accurate representation of the thermo-physical properties of supercritical solvent is considered by using the NIST Standard Reference Database 12. The conservation equations for mass, momentum, energy and species are numerically solved using implicit finite volume method. The effect of process parameters, such as initial state (pressure and temperature) of solvent and acoustic waves on the yield of solute extraction is also investigated numerically.  相似文献   

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