Research and Development: Applications

Liquid chromatography is now a fundamental process for the isolation, separation and purification of compounds. The design of this process is a very important stage in its development from laboratory to industrial scale, as it allows for determination if operating parameters. The process design is preceded by a series of experimental runs, in which the operating window can be determined. For this purpose, chromatographic columns with small volumes, i.e., 1 mL or smaller are used. Miniaturization of columns allows manufacturers to significantly speed up the experimental trials and reduce the use of expensive materials. A negative effect of column miniaturization is the increasing ratio of void volumes present in the chromatography setup (SVV) to the volume of the packed bed. The SVV consists of both the empty volumes of the extra-column volumes and the empty volumes of the intra-column volumes. Each component of the SVV differs in flow channel length, its diameter and curvature, which causes differences in velocity distribution in axial and radial directions and results in deformation of concentration profiles (chromatographic peaks). Neglection of these effect results in misinterpretation of the elution data and incorrect description of adsorption mechanism in chromatographic column. To avoid failure in the process design, the flow behavior is elution path should be quantitatively described. For this purpose, Computational Fluid Dynamics (CFD) method is the most suitable.
CDF enables not only to account the influence of the geometry of all elements of the chromatographic setup on the hydrodynamics and the shape of chromatographic peaks, but also provides possibility of additional analysis of broadening of the concentration profiles of eluting compounds. Insight into elution pattern that can be gained from the analysis of simulation results will allow the chromatographic process to be carried out in a highly efficient manner for both small- and large-molecule compounds (e.g., proteins).