Enantioseparation of racemic mandelic acid by simulated moving bed chromatography using Chiralcel‐OD column

Abstract

The chiral separation of the racemic mandelic acid ((R,S)‐MA) by simulated moving bed chromatography with columns packed with Chiralcel‐OD stationary phase is investigated experimentally and numerically. The transport dispersion model combined with the modified Langmuir isotherm was applied to predict the dynamic behaviour and separation performance of the SMB process. The Triangle Theory was used to obtain the complete separation region of the SMB operation. The influences of the switching time, loading, extract flow rate and column configuration on the SMB performance were also studied. The online monitoring system consisting of circular dichroism (CD) and UV detector in series was employed to measure the composition and purity of the extract and raffinate streams. Good agreement between the experimental data and model predictions proved the efficiency and reliability of SMB modelling and the Triangle theory in the design and operation of SMB chromatography. Experimental results show that purity and recovery at extract and raffinate port can reach 99% although not at the same time.

Enantiopurification of Mandelic Acid by Crystallization-Induced Diastereomer Transformation: An Experimental and Computational Study

“…Thus, screening of appropriate derivatives that satisfy these criteria is required if deracemization is to be applied. While various methods have also been reported for the chiral separation of mandelic acid such as using an enantioselective membrane, a simulated moving bed-crystallization process, chiral stationary phases, enzyme-catalyzed optical resolution, − diastereomeric salt forming system with resolving bases and cocrystallization, these processes are generally limited to 50% yield whereas our proposed purification route offers the advantage of having up to 100% yield because of the conversion of the unwanted diastereomer to the desired one. This eliminates the waste of raw material or the extra processing steps required to transform the undesired enantiomer to the desired one.…”

Optimal operation of batch enantiomer crystallization: From ternary diagrams to predictive control

“…Several studies have been performed in the analysis of the coupled simulated moving bed (SMB) chromatography‐crystallization process for enantioseparation (e.g., Ref. ) However, study of optimal control for a batch direct enantioselective crystallization process is scarce. Although a number of results on crystallization utilizing the optimization‐based control design model predictive control (MPC) have appeared in the literature (e.g., Ref.…”