A Study of Chromatographic Resolution of Enantiomers: Solvent Characteristics of Supercritical Fluid and Liquefied Gas

对映体的色谱分离研究：超临界流体和液化气的溶剂特性

基本信息

批准号：
62550696
负责人：
NITTA Tomoshige
金额：
$ 1.22万
依托单位：
Osaka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1987
资助国家：
日本
起止时间：
1987 至 1988
项目状态：
已结题

项目摘要

The present work concerns with the separation characteristics of the supercritical carbon dioxide and liquified propane as a mobile phase in chromatographic resolution of potically active isomers. Two enantiomers, trans-stilbene oxide and 1-(9-anthryl)-2,2,2-trifluoroethanol, were resolved by a column with a chiralcellulose derivative coated on a silica gel. The experimental results are summarized as follows.(1) Carbon dioxide, propane and hexane are in the order of high resolution; the order is in parallel to the diffusivity in each solvent.(2) The capacity ratio decreases with increasing the concentration of alcohols for the three solvents. It also decreases with increasing pressure in case of the supercritical fluid. These observations may be explained by the competitive adsorptions of solute and solvent molecules on active sites.(3) The separation factor significantly increases with decreasing temperature, and it changes a little according to the combination of major fluids and add … More ed alcohols. The relative stability of adsorbed enantiomers may be controlled majorly by the solutes-polymer interactions and secondly by the solutes-solvents interactions in the adsorbed phase.(4) The separation factor of enantiomers increases slightly with increasing pressure of the supercritical fluid, which corresponds to the decrease of alcohol concentration in the adsorbed phase.(5) In a low velocity region where molecular diffusion and fluid-mixing are predominant, the overall mass transfer resistance for polymer-coated silica gel is smaller than that for the naked gel; however, in a high velocity region, the polymer-coated silica gel shows higher resistance than the naked. There may be two plausible explanations: 1) increase of the tortuosity factor in the porous particle due to the inclusion of polymers 2) particle coalescence due to the polymers attached on the outside of particles. The fundamental research on polymer coating method will be necessary for improving column efficiency. Less

目前的工作涉及超临界二氧化碳和清算丙烷的分离特征，作为在阳性活性异构体色谱分辨率中的流动阶段。两种对映异构体，氧化苯甲酸酯和1-（9-Anththryl）-2,2,2-三氟乙醇，通过一柱在硅胶凝胶上涂有脊椎纤维素衍生物的柱子解决。实验结果总结如下。（1）二氧化碳，丙烷和己烷均为高分辨率的顺序；该顺序与每种偿付能力的难度平行。（2）容量比随着三种溶液的醇浓度而降低。在超临界流体的情况下，它也随着压力的增加而降低。这些观察结果可以通过在活性位点上固体和溶液分子的竞争性添加性能来解释。（3）分离因子随着温度的降低而显着增加，并且根据主要液体的组合而变化一点，并添加…更多的ED酒精。吸附的对映异构体的相对稳定性可以主要由太阳能聚合物相互作用来控制，其次，在吸附阶段的太阳能 - 溶剂相互作用。（4）映异构体的分离因子略微增加，随着超临界流体的增加，与含量相差的超临界流体的增加相对于ADSORPEEC阶段的降低，该阶段的降低（5）中的降低（5）。液体混合是主要的，聚合物涂层的二氧化硅凝胶的总体传抗耐药性小于裸凝胶的总传料。然而，在高速速度区域，聚合物涂层的硅胶显示出比裸露的耐药性更高。可能有两个合理的解释：1）由于包含聚合物的包含，多孔颗粒中曲折度因子的增加2）由于颗粒外部附着的聚合物而引起的颗粒聚合。对于提高色谱柱效率，必须使用有关聚合物涂料方法的基本研究。较少的