New Developments In Simulated Moving Bed Chromatography

In the last decade the concept of simulated moving bed (SMB) chromatography has been successfully applied in several fields, e.g. for the separation of enantiomers and the purification of pharmaceutical proteins. Often the separations were realized with the classical implementation of the process using four distinct zones and constant operating conditions (e.g. switching times, liquid phase velocities and solvent strengths). In order to further increase the potential of SMB chromatography, several more sophisticated modes of operation have been developed based on applying gradients and on dynamically varying certain parameters during the separation. Examples for the latter approach are the VariCol [1], PowerFeed [2] and ModiCon [3] processes. There are several interesting attempts to reduce the number of columns needed to realize the basic principle [e.g. 4]. Another promising alternative capable to enhance the process performance is based on the introduction of an enrichment step between zones I and II [5,6]. Besides treating binary mixtures, research increasingly focuses on continuous processes capable to perform multicomponent separations. To achieve separation of a ternary mixture different approaches have been suggested using increased numbers of zones (ranging from 5-Zone open loop up to 14-Zone closed loop setups [e.g. 7]). Recently, a 8-Zone closed loop separation unit was discussed utilizing an external enrichment step [8]. In the presentation will be also discussed the potential of different new strategies based on partial product collection and feed-back of fractions which do not fulfill required specifications [9,10]. The whole presentation intents to give a concise overview to demonstrate the large potential which exists to further improve the classical SMB concept. [1] M. Bailly, P. Adam, O. Ludemann-Hombourger, R.M. Nicoud, WO 2000025885 (2005). [2] Z. Zhang, M. Mazzotti, M. Morbidelli, Journal of Chromatography A 1006 (2003) 87. [3] H. Schramm, A. Kienle, M. Kaspereit, A. Seidel-Morgenstern, WO 2004014511 (2004). [4] R.C.R. Rodrigues, J. M. M. Araujo, P.J.M. Mota, Journal of Chromatography A 1142(2007) 69. [5] M. Bailly, R.M. Nicoud, P. Adam, O. Ludemann-Hombourger, US 2006124549 (2006). [6] G. Paredes, H.K. Rhee, M. Mazzotti, Industrial & Engineering Chemistry Research 45 (2006) 6289. [7] P.C. Wankat, Ind. Eng. Chem. Res. 40 (2001) 6185. [8] L.C. Keßler, A. Seidel-Morgenstern, Journal of Chromatography A 1126 (2006) 323. [9] Y.-S. Bae, C.-H. Lee., Journal of Chromatography A 1122(2006) 161. [10] L.C. Keßler, A. Seidel-Morgenstern, Journal of Chromatography A, submitted. © 2008 American Institute of Chemical Engineers [accessed December 11, 2008