Department of Chemical Engineering, Hanyang University, Haengdang-dong, Seongdong-gu, Seoul 133-791, South Korea.
J Chromatogr A. 2012 Sep 21;1256:46-57. doi: 10.1016/j.chroma.2012.07.091. Epub 2012 Aug 6.
For a three-zone simulated moving bed (SMB) chromatography with linear isotherms, the feasible set of operating parameters for complete separation is known to exist within a triangular region of the triangle theory that is formed in the operating parameter plane spanned by the flow-rate-ratios in the separation zones (II and III), which are commonly denoted as m(2) and m(3). Such an operating region for complete separation region, however, has been established only in the first quadrant (m(2), m(3)) plane, where m(2)>0 and m(3)>0, until now. In this study, a new complete-separation region was developed in the third quadrant (m(2), m(3)) plane, where m(2)<0 and m(3)<0, regarding a three-zone SMB process for the first time. The results showed that the new separation region created in the third quadrant (m(2), m(3)) plane took a non-triangular shape. The operating parameters within such a non-triangular separation region were capable of guaranteeing complete separation for an ideal system with no mass-transfer effects. For a non-ideal system with considerable mass-transfer effects, the operating parameters that were selected with a sufficient margin from the boundaries of the non-triangular separation region led to high purities. One of the noteworthy features in the pattern of solute migration for such case was that both low-affinity and high-affinity solutes reached their corresponding product ports after taking a turn around the SMB bed once. Finally, it was confirmed from the results of SMB optimization based on genetic algorithm and detailed model that the operating parameters in the third quadrant (m(2), m(3)) plane, if chosen properly, could ensure higher purities or higher throughput than the optimal operating parameters in the first quadrant (m(2), m(3)) plane.
对于具有线性等温线的三区域模拟移动床（SMB）色谱，已知完全分离的可行操作参数集存在于三角形理论形成的三角形区域内，该区域位于由分离区（II 和 III）中的流速比在操作参数平面上形成的，通常表示为 m(2) 和 m(3)。然而，到目前为止，这种完全分离区域的操作区域仅在第一象限（m(2)，m(3))平面上建立，其中 m(2)>0 且 m(3)>0。在这项研究中，首次针对三区域 SMB 工艺，在第三象限（m(2)，m(3))平面上开发了一个新的完全分离区域。结果表明，在第三象限（m(2)，m(3))平面上创建的新分离区域呈非三角形形状。在这种非三角形分离区域内的操作参数能够保证无传质效应的理想系统的完全分离。对于具有相当大传质效应的非理想系统，从非三角形分离区域的边界选择具有足够裕度的操作参数会导致高纯度。在这种情况下，溶质迁移模式的一个值得注意的特征是，低亲和性和高亲和性溶质在 SMB 床旋转一次后都到达它们相应的产物端口。最后，从基于遗传算法和详细模型的 SMB 优化结果中确认，如果选择得当，第三象限（m(2)，m(3))平面中的操作参数可以确保比第一象限（m(2)，m(3))平面中的最佳操作参数更高的纯度或更高的通量。
