A previous research confirmed the feasibility of using a size-exclusion tandem simulated-moving-bed (SMB) process in realizing the high-purity separation of neoagarohexaose from neoagarooligosaccharides (NAO) mixture. To promote the industrial application of such tandem SMB (named as “NAO-SMB” in this article) comprising two subordinate SMB units (Ring I and Ring II), we aimed at accomplishing its comprehensive optimization, which was carried out on the basis of a standing-wave- design method. It was found first that in a conventional frame where the same column length was set to be used in Ring I and Ring II under the column configuration of 2–2–2–2 in each ring, the separation sequence based on removing a larger-size impurity in Ring I and then smaller-size impurities in Ring II (S1 mode) led to higher throughput than the opposite separation sequence (S2 mode). By contrast, if the column lengths of the two rings were allowed to be set differently, the bed utilization of the S2 mode could increase more than that of the S1 mode, thereby causing the S2 mode to surpass the S1 mode in throughput. In addition, if the column configuration of each ring was allowed to be varied, the level of attainable throughput could be increased by allotting more columns in the enrichment zones containing the front and rear of product solute band in Ring I. Furthermore, it was confirmed that the simultaneous application of the aforementioned two methods (i.e., using different column lengths in two rings and placing more columns in the enrichment zones of Ring I) had an additional upward effect on each other. As a result, the optimized NAO-SMB under such frame, whose column length and configuration were 13.33 cm and 2–4-3–3 in Ring I and 18.67 cm and 2–3-5–2 in Ring II, could achieve 46% higher throughput than that under the conventional frame, and further lead to 133% higher throughput than the initial NAO-SMB reported in a previous study.

先前的研究证实了使用尺寸排阻串联模拟移动床 (SMB) 工艺实现新琼脂六糖与新琼脂低聚糖 (NAO) 混合物的高纯度分离的可行性。为了促进这种由两个下属SMB单元（Ring I和Ring II）组成的串联SMB（本文中称为“NAO-SMB”）的工业应用，我们旨在完成其综合优化，这是基于一种驻波设计方法。首先发现在常规框架中，在每个环中2-2-2-2的列配置下，Ring I和Ring II使用相同的列长度，基于去除环 I 中较大尺寸杂质然后去除环 II 中较小尺寸杂质的分离序列（S1 模式）导致比相反的分离序列（S2 模式）更高的通量。相比之下，如果允许两个环的柱长设置不同，S2模式的床利用率可以比S1模式增加更多，从而导致S2模式在吞吐量上超过S1模式。此外，如果允许改变每个环的柱配置，可以通过在包含环 I 中产物溶质带前后的富集区分配更多柱来提高可达到的通量水平。此外，已证实同时应用上述两种方法（即 在两个环中使用不同的柱长并在环 I) 的富集区放置更多的柱对彼此有额外的向上影响。因此，在该框架下优化的 NAO-SMB，其柱长和配置分别为 13.33 cm 和环 I 中的 2-4-3-3 以及环 II 中的 18.67 cm 和 2-3-5-2，可以实现 46吞吐量比传统框架下的吞吐量高 %，并进一步比先前研究中报告的初始 NAO-SMB 吞吐量高 133%。