Structured chiral adsorbent formed by cyclodextrin modified layered solid film

The film of carboxymethyl-β-cyclodextrin-intercalated Zn–Al layered double hydroxide (CMCD-LDH) has been prepared by in situ crystallization on a porous anodic alumina/aluminum (PAO/Al) substrate. This film can be used to enantioselectively separate racemic molecules, 1-phenyl-1,2-ethanediol (PED). The adsorption isotherms of enantioselective as well as non-enantioselective adsorption of PED by CMCD-LDH film have been investigated, and it was found that the Langmuir–Freundlich and Freundlich model can be, respectively, used to describe the two different adsorptions satisfactorily. Furthermore, the plane sheet diffusion model was successfully validated in this work. Diffusivities (D) of PED in CMCD-LDH film were determined from the Fickian diffusion model at various temperatures. As the structured CMCD-LDH film is conveniently used and exhibits high enantioselective adsorption ratio, it can be expected that this film could be feasibly applied in the field of industrial chiral adsorption and separation.