Comparison of Various Process Engineering Concepts of Preparative Chromatography

Abstract

Liquid chromatography utilizing porous solid phases (adsorption chromatography) is one of the most powerful and versatile methods of modern analytical chemistry. Its widespread application is due in part to the development of a broad range of combinations of solid stationary and liquid mobile phases. Normal phase and reverse phase chromatography with pure and chemically modified silica, respectively, affinity chromatography, can be cited as examples [1]. In addition to its use as an analytical method, chromatography is becoming increasingly important in the preparative scale for the isolation of pure substances in the pharmaceutical industry, in biotechnology, and in the production of fine chemicals. In many cases, the required purity criteria can only be met with chromatographic techniques, as in the resolution of racemates. From a process engineering viewpoint, a better understanding of concentration profile deformations caused by intended overloading of separation columns has recently been acquired [2]. In particular, this concerns the description of displacement and entrainment effects associated with the competitive adsorption. A series of alternative operating modes has been developed and used [3] to enhance yields and productivities. In spite of a number of attempted comparative studies [4], quantitative information about optimizing these processes is lacking. This article will compare four different process engineering concepts of preparative chromatography on the basis of a uniform theoretical model.

Optimization and Analysis of Possible Column Arrangements for Multicomponent Separations by Preparative Chromatography

“…A correspondingly detailed cost function will not be used here, since it would lead to highly specific results . In-depth discussions of this can be found in refs , , and .…”

“…The specific productivity, Pr, is often considered as the key parameter in preparative chromatography. ,, Pr is defined here as the mass flow rate of the intermediate target component of the complete column arrangement, ṁ 2,tot , divided by the volume of stationary phase contained in the N col columns: Pr = 1 N col ṁ 2 , tot false( 1 − ε false) V where V is the volume of a single column. For the given number of columns N col = 8, the optimization problem in this work can be written as ṁ 2 , tot → max s.t. Pu ≥ Pu min , Δ p ≤ Δ p max , V̇ ≤ V̇ max The constraints in eq account for practical conditions; i.e., upper limits are assumed for the pressure drop, eq , and for the pump flow rate(s) V̇ .…”

“…The specific productivity, Pr, is often considered as the key parameter in preparative chromatography. 4,30,31 Pr is defined here as the mass flow rate of the intermediate target component of the complete column arrangement, m ˙2,tot , divided by the volume of stationary phase contained in the N col columns:…”

Simulated moving bed technology to improve the yield of the biotechnological production of lactobionic acid and sorbitol

“…Some studies on the comparison between batch and SMB systems have been published (Heuer et al 1997;Strube et al 1998;Jupke et al 2002). It is widely known that the productivity from SMB processes is larger than that achieved by elution chromatography, and, moreover, compounds are recovered with lower degree of dilution.…”

Coupling Chromatography and Crystallization for Efficient Separations of Isomers

“…It is widely accepted that a countercurrent chromatographic separation, usually, exploits more efficiently the stationary phase and allows for a lower eluent consumption compared to a simple batch elution process (Heuer et al, 1998). Therefore, the chromatographic separation is done in this work by means of SMB chromatography.…”