The theoretical study of the effect of packing heterogeneity on HPLC by computational fluid dynamics

Abstract

SummaryBased on the assumption of a radial parabolic porosity distribution across a chromatographic column and an ideal distribution and collection system for the column, a theoretical study of the effect of heterogeneous packing on the behavior of chromatographywas conducted using Computational Fluid Dynamics (CFD) simulation. This study examined the development of the velocity distribution in columns with different porosity variations and different diameters, visualized the effect of velocity distribution on concentration profiles inside the column and the elutecl pulses at the exit and finally the column efficiency Therefore, this study is helpful to enhance the understanding to the effect of packing quality on chromatography The final result suggests that packing heterogeneity in current widely used chromatographic columns might seriously impair the separation efficiency of the colu mns.

Model column structure for the analysis of the flow and band-broadening characteristics of silica monoliths

“…Combining advanced numerical solver and grid generation routines, CFD software packages are namely ideally suited to solve the complete impulse and species conservation balances in complex domains with a high degree of accuracy. Since the dramatic increase in computational power of commercial personal computers and workstations over the last decade, CFD simulations have over the last decade become an important and widely accepted tool in the field of chemical engineering [11], and are now also gradually introduced into the field of chromatography [10,12].…”

Advantages of Perfectly Ordered 2-D Porous Pillar Arrays over Packed Bed Columns for LC Separations: A Theoretical Analysis

“…CFD packages are ideally suited to calculate the velocity field in complex geometries and provide a unique opportunity to obtain detailed velocity data for flows through spaces that are inaccessible for experimental measurement methods. CFD simulations have, therefore, also become an increasingly used design tool in the lab-on-a-chip field 10,11 and for the analysis of the flow pattern in chromatographic columns. − Since the flow in an LC column is without any doubt purely laminar and is, hence, purely deterministic, the CFD results can be made fully accurate, provided care is taken that the obtained results are independent of the grid shape and size.…”

Influence of Ring Frit Structure on Column Efficiency

“…The influence of column heterogeneity increases strongly with increasing column efficiency [6].Thus, packing heterogeneity had a considerable reduction on column efficiency especially on high performance columns. According to the experimentally observed velocity variations across columns by former researchers, the loss in column efficiency ranges around 10-50 % [7].…”

“…Combining column experiments with FLUENT simulation, Ching [23] confirmed the hypothesis that the frits of bad quality and the temperature gradient inside the chromatographic column could worsen the separation capability of the column, and temperature difference between the inlet and the wall could counteract the effect to some extent. Wu [7] and Yu [24] studied the effect of packing heterogeneity on HPLC and correctly predicted the nonlinear chromatographic band profiles by CFD simulation. Joris Vangelooven [25,26] used FLU-ENT software to aid the optimization of micro-pillar array columns and the distributors.…”