Continuous simulated moving

At present, the purification by chromatographic processes is the most powerful high-resolution bioseparation technique for many different products from the laboratory to the industrial scale. In this context, continuous simulated moving bed (SMB) systems are of increasing interest for the purification of pharmaceuticals or specialty chemicals (racemic mixtures, proteins, organic acids, etc.).This is particularly due to the typical advantages of SMB-systems, such as reduction of solvent consumption, increase in productivity and purity obtained as well as in investment costs in comparison to conventional batch elution chromatography [1]. 

Continuous simulated moving-bed (SMB) chromatography technique (reviewed by Francotte [423]) may be the method of choice for production scale. 

Several techniques, such as continuous simulated moving bed (SMB) as well as closed-loop and closed-loop... 

Strube,J. Haumreisser, S. Schmidt-Traub, H. Schulte, M. Ditz, R., Comparison of Batch Elution and Continuous Simulated Moving Bed Chromatography. Org. Process Res. Dev. 1998,2,305. 

Concerning its performance, steady-state recycling chromatography can be seen as an intermediate between simple batchwise or CLRC operation and continuous simulated moving bed (SMB) processes (Section 5.2). It combines lower complexity and equipment requirements than an SMB system with higher productivities and lower eluent consumption than obtained in batch chromatography. 

Mazzotti et al. (1996) studied the esterification of acetic acid with ethanol on a highly cross-linked sulphonic ion exchange resin (Amberlyst-15) in a continuous simulated moving bed reactor. The resin acted as catalyst as well as a selective sorbent simultaneously. They have studied the multicomponent sorption equilibria and swelling of the resin, as well as esterification kinetics with appropriate models. The thermodynamic and kinetic descriptions of the system have been combined to develop a fully predictive mathematical model of the chromatographic reactor. 

Since the 1960s the commercial development of continuous countercurrent processes has been almost entirely accompHshed by using a flow scheme that simulates the continuous countercurrent flow of adsorbent and process Hquid without the actual movement of the adsorbent. The idea of a simulated moving bed (SMB) can be traced back to the Shanks system for leaching soda ash (58). 

The theoretical performance of the commercial simulated moving-bed operation is practically identical to that of a system ia which soHds dow continuously as a dense bed countercurrent to Hquid. A model ia which the dows of soHd and Hquid are continuous, as shown ia Figure 7, is therefore adequate. 

Pais L. S., Loureiro J. M., Rodrigues A. E. (1997b) Modeling, Simulation and Operation of a Simulated Moving Bed for Continuous Chromatographie Separation of l,l -bi-2-naphthol Enantiomers, J. Chromatogr. A 169 25-35. 

Keywords Preparative chromatography, Simulated moving bed chromatography, Continuous separation technique, Triangle theory, Bioseparation... 

The performance of HPLC separations can be increased not only by the application of two- or multidimensional techniques but also by the use of simulated moving bed (SMB) [100-102] or true moving bed (TMB) techniques [103,104], SMB is a multicolumn separation technique allowing the continuous separation of analyses with higher productivity and smaller eluent consumption than the traditional single-column procedures. TMB... 

Adachi, S. J. Chromatogr. A, 658 (1994) 271. Simulated moving-bed chromatography for continuous separation of two components and its application to bioreactors. 

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