【作者】 徐霞；

【导师】 孙翠荣； 潘远江；

【作者基本信息】 浙江大学 ， 化学， 2011， 硕士

【摘要】 色谱峰拖尾会降低色谱柱效和分辨率,导致色谱分析的不准确性,是色谱研究中十分棘手的问题之一。本论文围绕“径向加压”的概念,设计了一套行星式离心柱色谱系统。具体内容如下：1.构建了离线式离心柱色谱系统,应用该系统获得了一对顺反异构体在离心色谱柱内的谱带展宽情况。通过比较分析离心色谱柱和传统色谱柱中的分离度的变化发现该系统可以有效地抑制色谱谱带展宽,提高分离效率。线性非理想色谱模型分析说明离心力抑制了色谱柱内的分子扩散。该系统的相关研究证实了“径向加压”对色谱过程的积极影响,为在线离心柱色谱系统的研究奠定了基础。2.构建了在线行星式离心柱色谱系统,应用该系统记录了三个保留时间不同的有机小分子化合物的色谱洗脱曲线,并比较分析了行星式离心柱色谱系统和传统的柱色谱系统的洗脱曲线的两个特征参数——不对称因子和拖尾因子。两个参数的减小说明该系统可以有效地改善色谱峰形拖尾。3.构建了行星式离心柱色谱系统的理论模型,通过该模型分析了行星式离心色谱柱中的任意一点处的总加速度的大小和方向。总加速度的方向变化说明行星式离心色谱柱内的流动相存在多方向的径向循环流动,降低了色谱柱内的径向异质性,最终改善了色谱峰形拖尾。更多还原

【Abstract】 Peak asymmetry, which is one of the knotty problems in chromatography study, brings about undesirable effects in both physicochemical studies and application of chromatography. This study aimed to establish an effective method to reduce peak asymmetry by introducing a radial force on the column. The detail is as follows.1. An off-line centrifugal column chromatography system was installed. With this system, the band broadening of two cis-trans-isomers was obtained. Comparing with the classic chromatography, the separating degree in the centrifugal chromatography system was improved. An analysis with the theoretical model showed that the diffusion coefficient was reduced by the centrifugal force in the radial direction.2. An on-line planetary centrifugal column chromatography system was first brought forward and implemented. With this system, the elution profiles of three compounds with low molecular weight were recorded under different rotation speed. The asymmetry parameter and tailing factor were compared and the results implied that the planetary centrifugal column chromatography system could improve peak tailing of elution profiles more compared with the classic column chromatography.3. A physical and mathematical model for the planetary centrifugal column chromatography system was deduced. The theoretical model suggests that total acceleration (α) acting on an arbitrary point in the planetary centrifugal column may cause a radial flow with multi-directions, which could lead to a radial circulation of the mobile phase and the analytes. The circulation could relax the column radial heterogeneity and result in an improvement of peak asymmetry ultimately.更多还原