Optimization of Supercritical Fluid Chromatography for Enantioseparations

Supercritical fluid chromatography (SFC) is a technology that is finding increasing applications in enantiomer separations. The properties of supercritical CO2, the most commonly used mobile phase, make the process efficient and results in significant reduction in organic solvent consumption, making it a green technology.

In this work single and multi-objective optimization of supercritical fluid chromatography system for enantio-separations of flurbiprofen, a key non-steroidal anti-inflammatory drug (NSAID). The optimization was carried out based on experimentally verified mathematical model and isotherm parameters with a wide range of operating conditions such as flow rate, solute concentration, injection volume and modifier composition [1]. For single objective, the optimization aims to maximize the productivity. For multi-objective, it intends to simultaneously maximize the productivity and minimize the solvent consumption. Optimal solutions were obtained for three different operation modes, namely, isocratic, step gradient and linear gradient. For both single and multi-objective optimization, high flow rate and low purity constraint tend to give high productivity under all three modes. Low purity constraints also decrease the solvent consumption which can be observed from the Pareto profile. It is shown that SFC offers productivities comparable to those generally associated with complex multi-column processes (e.g. SMB) and the reduction in solvent consumption are an added advantage. Finally, the experimental verification of optimization results are discussed.

References

1. C. Wenda, A. Rajendran, J. Chromatogr. A, in press.