A Zn(II) pillared-layer ultramicroporous metal-organic framework with matching molecular pockets for C2H2/CO2 separation

Similar sizes and boiling points of acetylene (C2H2) and carbon dioxide (CO2) make CO2 separation from C2H2/CO2 mixtures challenging. In this work, a pillared-layer ultramicroporous Zn-mipa-datz material featuring a C2H2-matching cavity was successfully prepared to achieve high-efficiency C2H2/CO2 separation. The separation performance of Zn-mipa-datz on C2H2/CO2 mixtures was investigated through gas adsorption isotherms and dynamic breakthrough experiments. Zn-mipa-datz possessed high C2H2 separation efficiency for C2H2/CO2 mixtures. The molecular simulation demonstrated that the strong C2H2-host interaction was achieved by the synergistic effect of C-N electrostatic interactions and C-H center dot center dot center dot N H bonds.