Solid membranes for chiral separation: A review

Most drugs used daily are chiral compounds and exist in the form of racemic mixtures, so the separation of enantiomers has always been concerned because of their similar chemical properties but different pharmacological activities. Many classic technologies such as chiral synthesis and chromatographic separations have been widely used for selective enantiomeric separation. Membrane separation without phase change and additives, as an emerging chiral-separation protocol with high efficiency, simple, low energy consumption, and continuous automation operation, has great potential in the field of chiral separation. Currently, many membranes based on polymer, carbon nanomaterials, metal organic frameworks, and some other inorganic materials have been reported in chiral separation, but are rarely summarized systematically. Therefore, this review focused on synthesis and application of these new chiral solid membranes from 2016 to 2020, and the advantages and disadvantages faced by such materials have been summarized and discussed systematically, which is hopeful to promote the advance of chiral separation using solid membranes.