Dynamic simulation of simulated moving-bed chromatographic processes for the optimization of chiral separations

Abstract

Mass separation by simulated moving-bed (SMB) chromatographic processes is influenced by a number of different parameters. Therefore planning and realization of pilot experiments as well as process design and optimization are complicated tasks. Todays new applications of SMB processes in the pharmaceutical, agrochemical and biochemical production have to deal with concentration-dependent capacity and separation factors near unity and have to be operated at high resolution, yield and purity. Therefore rigorous dynamic process modelling combined with a few characteristic experiments to determine the model parameters which describe axial dispersion, multi-component equilibrium with interference of the components and mass transfer resistances has proved necessary. The detailed dynamic model which has been developed is a crucial aid in understanding malfunctions of pilot plants, optimizing process conditions and specifying start-up procedures for SMB processes. This paper presents a first study to verify the rigorous dynamic SMB process model by experimental data of a SMB process. The proposed modelling approach, method of model parameter estimation and process optimization are verified by experimental data of an enantioseparation. The model parameters are estimated by experiments at an analytical HPLC single column and a pilot pulse through the SMB columns. Experimental process data are used to compare the results of process simulations with measured axial concentration profiles.