Evaluation of the optimal performance of ModiCon and ModiCon+VariCol simulated moving bed variants

The interest in the simulated moving bed (SMB) technology lies in its variants. Some of them that have a high potential to increase the performance in enantioseparations are the ModiCon and the ModiCon+VariCol. These variants are based on the modulation of feed concentration and a combination of feed concentration and length of zones modulations. The concept of the ModiCon process in the literature is that it can be applied only for systems described by nonlinear isotherms. However, there are no numerical or experimental studies that prove that. On the other hand, the hybrid operation of ModiCon+VariCol can be used in systems with a low number of columns due to the flexibility in the use of columns, but it has been little explored. In this work, the maximal performance of the ModiCon process was compared with the SMB process for a linear isotherm. Additionally, the ModiCon+VariCol process was evaluated in systems with a low number of columns. The enantioseparation of guaifenesin was considered as a case study. The result shows that the ModiCon process can also be applied with high performance in systems described by linear isotherms. In the evaluation of the ModiCon+VariCol process for unequal product purity, it was found that the hybrid operation with 3 columns showed a higher throughput and productivity than the SMB process with 6 columns. The productivity of the ModiCon+VariCol was more than three times higher than the conventional operation.