Mass transfer and separation criteria for high‐speed countercurrent chromatography

Abstract

in Wiley Online Library (wileyonlinelibrary.com).High-speed countercurrent chromatography (HSCCC) is a versatile technique for preparative separations of a wide variety of solutes. For optimization of operating conditions, prediction of separations, and scale-up study, a model is needed to describe the effluent concentration profile, which determines the separation efficiency (mass transfer, mixing, and partitioning) and the resolution between peaks. A transferdispersive model is proposed to describe the effluent profile based on the assumption that the retention of a peak is caused by partitioning over two phases, and peak broadening is caused by axial dispersion and mass transfer limitation. In this work, mass transfer was investigated by comparing model simulations to experimental data. One generalized correlation of overall mass transfer coefficients was derived. Based on the correlations of axial dispersion coefficients in our previous work and mass transfer coefficients in this study, the model predicts the elution concentration profile well. Furthermore, separation criteria were proposed to predict the separation of two adjacent solutes, and they were verified using literature data.

Methodology for optimally sized centrifugal partition chromatography columns

“…We propose here to introduce a correlation between dimensionless numbers that include: the two-phases properties, the operating conditions and the CPC cells size (on the Vashy-Buckingham theorem basis [20]). This approach was previously proposed by Zhao et al [21] to control scale changes in CCC using the Sherwood number (Sh), the Schmidt number (Sc) and the rotational Reynolds number (Re). The correlation for CPC will be fitted to a large panel of experimental separations, giving a correlation for mass transfer efficiency prediction, whatever the scale or the conditions are.…”

Recent progress in separation prediction of counter‐current chromatography

“…When comparing with the elution‐CCD model, the outcomes of the two‐phase longitudinal diffusion model were continuous but not connected by independent points of concentration from each test tube [78]. The influence of longitudinal diffusion could also be expressed by the total diffusion coefficient in chromatographic column such as Peclet number [79]. Relation equation of longitudinal diffusion coefficient and the number of theoretical plates was obtained by mathematical method [80].…”

Tubing modifications for countercurrent chromatography (CCC): Stationary phase retention and separation efficiency

“…This is due to the limited number of repetitive mixing and de-mixing processes and mass transfer between the liquid phases which impairs the resolution and separation efficiency and leads to peak broadening [18].…”