Layered double hydroxide nanosheets embedded β-cyclodextrin composite membranes with enhanced chiral separation performance

The technologies for enantiomeric resolution are essential to the development of pharmaceutical indus-try. The membrane technology has great potential in chiral separation owing to its low cost and high throughput; however, the enantioselective of membrane is limited by the thickness of the active layer, which is closely related to the number of theoretical separation plates. In this work, the layered double hydroxides (LDH) are synthesized by hydrothermal process and then vacuum filtrated with b-cyclodextrin (b-CD) and polyvinyl alcohol (PVA) on a porous substrate to fabricate chiral selective mem-branes. 2D channels with increased number of separation stages are formed in the selective layer after heat post-treatment. The enantiomeric excesses value is enhanced from 10.95% to 24.32% for racemic L/D-tryptophan resolution. This work provides a new approach for designing high performance chiral separation membranes from the aspect of increasing the transport path.(c) 2023 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

Automated summary

Membrane technology has great potential in chiral separation, but its selectivity is limited by the thickness of the active layer. In this study, layered double hydroxides were synthesized to fabricate chiral selective membranes. By increasing the number of separation stages through heat post-treatment, the enantiomeric excess value was enhanced.