Abstract:

The sequential simulated moving bed has a variety of switching modes, low energy and water consumption, and can achieve continuous and efficient separation and purification of multi-component and difficult-to-separate systems. Previous studies have shown that the sequential simulated moving bed cannot simultaneously take into account the performance of purity and solvent consumption, so this project mainly focuses on improving the separation performance through structural regulation and optimization, furthermore developing a new operating mode with universal applicability. Firstly, xylooligosaccharide syrup was selected as the target system, and DOWEX MONOSPHERE^TM 99/310 K⁺ resin was used as the stationary phase to complete the corresponding separation experiment and process simulation in order to verify the accuracy of the model. The switching sequence control and switching mode modification of the sequential simulated moving bed were carried out by process simulation, and then the purity, yield and water consumption of the final product were compared. The results show that the new “circulation-feed-elution” mode performs well and can control water consumption while ensuring high purity and yield. Compared with the traditional structure of “feed-cycling-elution”, the purity and yield of the target product were increased by 33% and 37% respectively under the same operating conditions, and the water consumption was reduced by 2.79 ml/min. In addition, different modification methods can also regulate the separation performance, improve the diversity of products, and reduce the production cost. This study provides ideas and references for the industrial application and modification of the sequential analog moving bed.

Key words: sequential simulated moving bed, structure regulation, mathematical modeling, separation, adsorption

摘要：

顺序式模拟移动床切换模式多变，能耗水耗低，可实现多组分、难分离体系的连续性高效分离纯化。前期研究表明，顺序式模拟移动床无法同时兼顾纯度和溶剂消耗等性能，为此计划通过结构调控与优化，提升分离性能，开发一种具有普适性的新型操作模式。首先选择低聚木糖糖浆作为目标体系，使用DOWEX MONOSPHERE^TM 99/310 K⁺ 树脂作为固定相，完成相应的分离实验及过程模拟，以验证模型的准确性。通过过程模拟对顺序式模拟移动床子步骤进行切换顺序调控和切换模式改型，并比较其产品纯度、收率、水耗等指标。结果表明，新型“循环-进料-洗脱”模式表现优异，可在控制水耗的同时保证较高的纯度和收率，且与传统结构“进料-循环-洗脱”相比，相同操作条件下目标产物的纯度和收率分别提升了33%、37%，水耗下降了2.79 ml/min。此外，不同改型方式也可调控分离性能，提高产品多样性，并降低生产成本。本研究为顺序式模拟移动床的工业化应用与改型研究提供了思路与参考。

关键词: 顺序式模拟移动床, 结构调控, 数学模拟, 分离, 吸附