Resolution in CCC: The Effect of Operating Conditions and Phase System Properties on Scale‐Up

Abstract

Being able to accurately predict the eluted volume of a substance with a known distribution ratio will depend on accurately knowing the retention volume of the stationary phase. Sample resolution depends on a number of factors that are not so easy to predict: the properties of the phase systems, the number of mixing and settling cycles per unit time, the rate of mass transfer during mixing, and the quality of mixing between the phase systems. The extent of mixing between the phases will, in turn, depend on the flow rate of the mobile phase and the ''g'' field acting across the stratified phases within the coiled tubing. A systematic study is made of how sample resolution changes with the key operating variables associated with scale-up: the mobile phase flow, the bore of the tubing, and the rotational speed. It shows how the commonly accepted characteristic, good 1475 resolution at low flow and poor resolution at high flow, slowly changes as tubing bore increases to one of poor resolution at low flow rising to optimum resolution at high flow and a slow decline in resolution at very high flow. Furthermore, it goes on to show that, as phase system physical properties change when moving from hydrophobic phase systems to more polar hydrophilic ones, the optimum resolution remains in a similar speed and flow range. It also shows that the key variable for scale-up, the throughput of sample in kg=hour, increases significantly as mobile phase flow increases, provided the rotational speeds are high enough. Optimum throughput has not yet been reached, which is extremely promising for realising process scale CCC.

Numerical model for the investigation of countercurrent chromatography

“…Two types of elution modes are introduced into the calculations: normal‐phase elution mode and reversed‐phase elution mode 25. Especially, the combination of these two modes is quite useful in the purification of bioactive components from the Chinese herbal medicine, since most herbal systems of multiple active components are complex and CCC is a technology which could be scaled‐up linearly 26–29.…”

Discrimination and Experimental Study of HSCCC Operational Modal based on LSCF

“…Based on the J-type HSCCC virtual prototype, M. Li and Z. Li et al [6][7] constructed the finite element model of the planetary frame and central shaft drive system, performed low-order intrinsic mode analysis, and obtained the first six-order intrinsic frequencies and the corresponding mode of vibration. Sutherland and Chen et al [8][9] investigated the effect of structural parameters on separation efficiency and demonstrated a direct correlation between the structural parameters and separation efficiency [10] . Fang et al [11] studied the deformation of the bearing contact region of the planetary structure.…”

Enantioseparation of 2‐(4‐chlorophenyl)succinic acid by countercurrent chromatography and investigation of injection volume on resolution

“…Thermodynamic factors in enantioseparation composed of separation temperature, type and concentration of chiral selector, and pH of aqueous phase, which can be investigated by enantioselective liquid–liquid extraction. For kinetic factors, including the bore of the tubing [16], stationary phase retention [17], the linear velocity of mobile phase [18], and the rotational speed [19], have been well studied in the past years. All the published literatures reporting on peak resolutions were about separation of natural products.…”