Relationship between trans-column eddy diffusion and retention in liquid chromatography: Theory and experimental evidence

被引:59
作者
Gritti, Fabrice [1 ]
Guiochon, Georges [1 ]
机构
[1] Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA
基金
美国国家科学基金会;
关键词
Packed column; Mass transfer resistance; Eddy diffusion; Trans-column eddy diffusion; Trans-column velocity biases; Local electrochemical detection; Benzoquinone; HETP; Uracil; Acetophenone; Toluene; Naphthalene; Core-shell particles; Kinetex-C-18; EXTERNAL MASS-TRANSFER; TRANSFER KINETICS; TURBULENT-FLOW; PERFORMANCE; COEFFICIENTS; DISPERSION; EFFICIENCY; VELOCITY; SHELL;
D O I
10.1016/j.chroma.2010.07.029
中图分类号
Q5 [生物化学];
学科分类号
071010 ; 081704 ;
摘要
Experimental results demonstrate that trans-column eddy diffusion depends on the retention of compounds. The combination of elution profiles recorded in different points of the exit column cross-section and of the height equivalent to a theoretical plate (HETP) of small molecules clearly show a strong link between retention and column performance in liquid chromatography. These results validate a new model of trans-column eddy diffusion in packed columns. The contribution to the column HETP of the trans-column eddy diffusion term decreases with increasing retention factor from k' = 0 to k' = 3 above which it becomes negligible. The best column performance in RPLC is observed for the most retained compounds. This is due to the combination of the lack of a residual trans-column eddy diffusion contribution and the vanishing contribution of the instrument to band broadening. (C) 2010 Elsevier B.V. All rights reserved.
引用
收藏
页码:6350 / 6365
页数:16
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