(320r) Effect of Selectivity on Partial Feed Operation for Four-Zone Simulated Moving Bed Chromatography

Simulated moving bed (SMB) chromatography is a continuous and effective separation process for valuable materials such as enantiomers [Zhang et al., 2004; Schulte and Strube, 2001]. Hence, it has become a widely used separation method. Zang and Wankat (2002) suggested a partial-feed concept to improve the SMB performance. The partial-feed operation means that the feed is introduced into the SMB system during part of a switching period. They showed that this partial-feed operation significantly improves the efficiency of a four-zone SMB with one column per zone in case of a large selectivity (≈2.43) system. In this study, the ″partial-feed″ is applied to five binary systems, which have different selectivities, to investigate the effect of selectivity on the ″partial-feed″ SMB at various operating conditions. In addition, the ″partial-feed″ operation is rigorously investigated for the four-zone SMB with one or two columns per zone in view point of six performance parameters (purity, major product concentration, productivity, eluent consumption, enrichment, and recovery). Especially, all the behaviors of the performance parameters are explained in detail based on the cyclic steady-state column profiles.